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167 Cards in this Set
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Parts, epithelium |
Lip - HE Lip has 3 parts, cutaneous part(right) red part(top) and mucosal part(left). Cutaneous part - Stratified squamous keratinizing epithelium *Layers of keratinizing epithelium *Malphigian layer *Stratum granulosum contains keratohyalin granules giving it the deep-blue staining - Hair follicle, sebaceous glands (Holocrine), and sweat glands (merocrine) - Describe and draw merocrine and holocrine secretion Red part or red margin - Stratified squamous keratinizing epithelium *very thin and with no glands * Alot of ct papilla - Meissner corpuscle are found in the ct papilla -> increased sensitivity - Tactile function is very important -> nerve endings - The deep penetration of the ct papilla into the epithelium gives this part the red color, this combined with the extensive vasculation and thin epithelium. - if the blood is not oxygenated enough (cyanosis), this will cause them to look blue Oral mucosa part - Stratified squamous non-keratinizing epithelium - Find salivary gland with merocrine secretion * Mostly mucous glands - Layers of non-keratininzing epithelium Mucocutaneous junction - vermillion border The junction between keratininzing and non-keratinizing zone. stratum granulosa will suddenly end. Beyond the junction where the stratum granulosa disappears we can now see nucleus in the superior layer of the epithelium. In the middle of the tissue we find skeletal muscle, connective tissue, vessels and nerves. (m. Orbicularis oris and depressor or levators of inf/sup lip.) Melanin pigments can be seen in epithelium as reddish-brown |
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Parts, glands, ducts |
Parotid gland - HE - 25% of salivary Biggest gland of the salivary glands Serous alveoli only - Compound tubolalveolar glands - drawe - Merocrine mechanism Between serous alveoli scattered fat cells are seen, these increase with age. Lobulated organ, seperated by ct septa contain ducts, vessels and nerves. Ducts in ct. septa - interlobular ducts, with pseudostratified or stratified columnar epithelium Ducts inside lobules -> intralobular ducts 1. Intercalated ducts - small - Lined with simple cuboidal epithelium - Drain into larger intralobular ducts - Myoepithelial cells -> beginning of duct system 2. Secretory/striated or salivary ducts - Large - Lined with simple columnar epithelium - secretes Potassium K+ and HCO3- and reabsorb Na+ and immunoglobins. - Named striated because on the base of the columnar cells we find rows of mitochondria sitting in the fold used to provide the energy requirements for active transport. - In the connective tissue around the duct we can see plasma cells, these produce immunoglobulins which are absorbed by nearby acinar cells and secreted. - They modify the composition of saliva- making it hypotonic - Stained very eosinophilic due to their high concentration of mitochondria Serous glands - Blueish, with basophilic cytoplasm - Cells produce digestive enzymes, needs ER for synthesis, therefore basophilic staining. - Round nucleus in center of cell - Very narrow lumen, almost not visible - Compound tubuloalveolar glands, merocrine secretion Secretes enzyme - Amylase - carbohydrates - Lysozyme - bacteria - Lactoferrin - bacteriostatic effect Facial nerves passes through |
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Secretory ducts in parotid gland |
Lined with simple columnar epithelium Secretes potassium, K+, and absorbs sodium and immunoglobins. These ducts are also called striated ducts since the base of the columnar cells are covered in rod like mitochondria sitting in the folds of the cell membrane. These allow the active transport in these cells. |
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Parts, glands, ducts |
Submandibular - He - 70% Submandibular gland is lobulated organ, the lobules are separated by ct. septa. Contains ducts, nerves and blood vessels. Lobules consist of mixed salivary glands -> 75% serous and 25% mucous Serous demilunes are mucous glands with a cap shape serous glands covering them. Duct system is similar to parotid, but intercalated ducts are shorter, and striated ducts are longer. 1. Intercalated ducts - small - Lined with simple cuboidal epithelium - Drain into larger intralobular ducts 2. Secretory/striated or salivary ducts - Large - Lined with simple columnar epithelium - secretes Potassium K+ and HCO3- and reabsorb Na+ and immunoglobins. - Named striated because on the base of the columnar cells we find rows of mitochondria sitting in the fold because of this active transport. - Stained very eosinophilic due to their high concentration of mitochondria Mucous glands - White cytoplasm, contains a lot of carbohydrates -> mucin -> makes saliva sticky and slimy. - Flat nucleus, nucleus is located in the outer part of the cell, against basal membrane. - Produce slimy saliva which prevents mouth from drying out. - Compound tubuloalveolar gland, merocrine secretion |
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Parts, glands, ducts |
Sublingual - He and PAS-H - 5% Sublingual gland is lobulated, the lobules are separated by ct. septa Consist of 1/3 serous and 2/3 mucous, which are compound tubuloalveolar glands. Many serous demilunes in this gland, most of the serous glands are seen as semideminules. Simpler ducts system than in the other salivary glands. Few intralobular ducts, because they are short. Interlobular ducts may be seen. Intralobular ducts of sublingual - Equiliant of striated ducts - Does not have basal striation, due to the lack of basal infoldings and mitochondria. Intercalated ducts of sublingual - Very short,flattend or low columnar Some slides you can see mucous membrane of oral cavity - non-keratinizing stratified epithelium. In the connective tissue stroma we find a large presence of lymphocytes and plasma cells - plasma cells produce salivary IgA Some slides you can sen see submandibular ganglion, an autonomic ganglion of the parasympathetic nervous system. Fibers carried 1. Sympathetic fibers frome external carotid plexus, via facial -> not synapse 2. Preganglionic parasympathetic fibers via chorda tympani and lingual n -> synapse in ggl. 3. Preganglionic parasympathetic oral mucosa and salivary glands |
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Parts, glands, ducts |
Sublingual gland - PAS-H PAS-H staining the mucous glands gets a dark purple color because of high carbohydrate content -> mucein Basal membrane that surrounds the serous gland is better visible because the lamina fibroreticularis of the basement membrane are PAS-positive |
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Parts, inorganic/organic component |
Ground tooth fuchsin Enamel - yellow/brown - Composed of enamel rods, which are in the shape of keyhole - Enamel rods wil span the full thickness of the enamel layer - Enamel covers everything visible above the anatomical crown - incremental lines of Retzius -> growth rings - 96% inorganic components -> CaPO4 - 4% organic components -> proteoglycans and glycoproteins - Enamel is thickest at cusps, and thinner at neck, covered by gingiva - Cannot be replaced after, but is influenced by secretion of salivary glands - Produced by ameloblasts, enamel organ is formed by ectodermal epithelial cells - Tomes processes are found at the apical pole of ameloblasts Dentin - between pulp cavity below and enamel above - Thickest part and innermost part of teeth. - Secreted by odontoblast, created from neural-crest predontoblasts - Apical surface of odontoblast is contact with the forming dentin, while the inner surface forms a epithelial layer - Layers of odontoblast will retreat as dentin is laid down, leaving processes embedded in the dentin in narrow channels called dentinal tubules * Toms fibers - After the receding a wave of mineralization follows - Radial black or purple striations -> Dental caniculi with Tom´s fibers, former occupied by odontoblasts - 80% inorganic - 20% organic - collagen fibers and ground substance. Pulp chamber - contains vessels, nerves and some ct Interglobular space - artefact in the dentin caused by shrinkage of organic compoents Cementum - not seen on this slide - Very similar to one, 65% non-organic - Covers the root of the teeth that fits in the alvolus - Produced by cementoblast - large cuboidal cells *Secretes cementoid, which undergoes mineralization - Cementoblast will become incorporated in cementum becoming cementocytes, and closely resemble osteocytes. *Lacunae and canaliculi in the cementum contain cementocytes and their processes - Very similar to bone, intercellular structure is produced by cementocytes. - Cellular cementum found close to apex - The gap between cementum and alveolus is filled by ct of periodontium, contains fibroblast/cytes and collagenous fibers -> Sharpeys fibers60% inorganic components, 40% organic components Acellular cementum - Thin, shiny clear layer around the dentin, close to the neck. - Thinner than cellular cementum - Sometimes there are artificial cracks -> fuchsin spots |
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Parts, inorganic/organic component |
Cementum - Very similar to bone, intercellular structure is produced by cementocytes.- Cellular cementum found close to apex - The gap between cementum and alveolus is filled by ct of periodontium, contains fibroblast/cytes and collagenous fibers -> Sharpeys fibers60% inorganic components, 40% organic components Acellular cementum - Thin, shiny clear layer around the dentin, close to the neck. - Thinner than cellular cementum - Sometimes there are artificial cracks -> fuchsin spots.. |
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Cellular cementum at the apex of the root Cementocytes |
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Acellular cementum in the root, close to the nech of the tooth. The acellular cement layer is a bright white narrow stripe. |
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What is found up and to the left on this slide? |
Shows incremental lines of retzius - growth rings |
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Show: Dentin, enamel, pulp cavity |
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Early development - Bell stage - HE 1. Developing tooth 2. Oral mucosa 3. Row of epithelial buds - remnant of the dental lamina connects the enamel organ to the oral mucosa 4. Inner enamel cells - Columnar cells, will later be named ameloblast or odamanblasts - Produce enamel 5. Outer enamel cells -> ectodermal origin - Dental follicle Ct - Surrounds the enamel organ and dental papilla - Will later be important for forming cementum and periodontium 6. Cervical loop of the enamel organ - Later form the Hertwig´s root sheath by inducing the formation of odontoblast in root region. Essential for root development 7. Stellate reticulum - Derived from epithelial cells in the inside of the dental bud 8. Dental papilla - Cavity of the bell is filled with mesenchyme - Develops from neural crest, ectomesenchyme 9. Odontoblast - columnar cells next to the inner enamel cells - Produce dentin - Cells derived from mesenchymal cells in dental papilla |
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Layers of keratinizing epithelium |
1. Stratum basale 2. Stratum polygonale 3. Stratum granulosum 4. Stratum lucidum 5. Stratum coneum - stratum compactum - stratum disjunctum |
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Layers of non-keratinizing epithelium |
1. Stratum basale 2. Stratum spinosum/polygonale 3. stratum pianocellulare |
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What are the different salivary glands? |
1. Parotid gland - serous only 2. Submandibular - Serous and mucous, but mostly serous 3. Sublingual - Mucous and serous, but mostly mucous Less ducts in sublingual. Compound tuboalveolar glands, with merocrine secretion |
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Division of glands |
Glands -> Endocrine or exocrine Exocrine -> endoepithelial or exoepithelial Exoepithelial -> unicellular or multicellular or secreting surface |
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Saliva |
Volume 1-1.5 L 70% submandibular, 25% parotid, 5% sublingual pH: 5.8-7.9 Composition - Electrolytes -> Na+, K+, HCO3, Cl-, Ca++, Mg, F, PO4 - Organic components -> Proteoglycans, glycoproteins, lyzozyme, lactoferrin, LgA, amylase etc Regulated by autonomic nervous system - Parasympathetic: induces water-rich saliva, during mastication - sympathetic: less volume, more viscous during stress |
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How is ground tooth prepared? |
Tooth cut into 1-2mm thick plates, which were individual grounded on special glass plates, and polished until transparent. then immersed into fuchsin, that filled all the empty spaces |
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What is the origin and function of Hertwig´s root sheath? |
Origin is the cervical loop It´s essential for development of root, by inducing the formation of odontoblast in the root region |
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Early development azan staining Similar to He stained slide, but colors are different. Dentin is blue and enamel is red. Show 1. Developing tooth in bell stage 2. Oral mucosa 3. Row of epithelial buds - remnant of the dental lamina connects the enamel organ to the oral mucosa 4. Inner enamel cells - Columnar cells, will later be named ameloblast or odamanblasts - Produce enamel 5. Outer enamel cells -> ectodermal origin - Dental follicle Ct - Surrounds the enamel organ and dental papilla - Will later be important for forming cementum and periodontium 6. Cervical loop of the enamel organ - Later form the Hertwig´s root sheath by inducing the formation of odontoblast in root region. Essential for root development 7. Stellate reticulum - Derived from epithelial cells in the inside of the dental bud 8. Dental papilla - Cavity of the bell is filled with mesenchyme - Develops from neural crest, ectomesenchyme 9. Odontoblast - columnar cells next to the inner enamel cells - Produce dentin - Cells derived from mesenchymal cells in dental papilla |
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What are the layers? |
Tooth development - advanced - He At the tip of the tooth the stellate reticulum disappeared, but we can see it on the lateral sides. Inner to outer 1.Dental papilla 2. Odontoblast 3. Predentin 4. Dentin 5. Enamel 6. Ameloblast 7. Stellate reticulum on lateral sides - Disappeared on sides 7. outer enamel cells |
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Tooth development - late phase - HE Later stage, so we can see dentin and predentin. - Predentin is ligther area, next to odontoblast - Calcified dentin are darker pink Enamel is the narrow purple covering dentin |
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late tooth development - azan Similar to previous He stained Dentin is blue, enamel is red |
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Layers from left to right |
Layers from left to right 1. Mesenchyma of papilla of tooth 2. Columnar, eosinophilic odontoblast 3. Dentin, close to odeontoblast - Lighter pink is predentin 4. Enamel -> Dark-purple 5. Ameloblast - Columnar cells 6. Stellate reticulum - star shaped cells 7. External enamel cells 8. Dental follicle |
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How many deciduous teeth, names and pattern? |
10 decidous teeth One medial incisor, one lateral incisor, one canine and two molar |
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How many permanent teeth, names and pattern of emergence? |
32, 8 in each quadrant, and 4 quadrants 2 incisive 1 canine 2 premolar 3 molar |
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What do we seen on the bottom and above? |
Bottom: Papilla dentis
Above: Odontoblast See tomes fibers reaching into the dentinal tubules in the predentin - Dentinal tubules seen as lighter stripes predentin |
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Tongue Fili- and fungiform papillae HE Tongue is made up of mostly skeletal muscle, covered by mucous membrane. The mucous memb. consist of epithelium mucosal and underlying ct, lamina propria. The epithelium is stratified squamous non-keratinizing epithelium Lamina propria sens ct. papillae into the epithelium surface epithelial projections gives the tongue a velvety look Filiform papilla - most common - Tall and narrow - More numerous, covering dorsum of tongue - No taste buds - May have keratinizing on tips -> whitish appearance - Function -> transmit tactile information, nerve endings Fungiform papila - Shorter and wider - Fewer, and located mostly on edge of tongue - Mushroom shaped epithelial projection - Contains taste buds on lateral and superior aspects - Appear as small red dots on the surface of tongue, because the epithelium is much thinner, and the underlying ct is highly vascularized. - may observe a deep sulcus on the sides of the papilla -> caliculi gustatorii Main bulk of tongue - skeletal muscles running in three perpendicular directions 1. sup and inferior longitudinal 2. Vertical muscle of tongue 3. Transverse muscle of tongue - Between muscle fibers we will find fat cells and mixed salivary glands+ducts, blood vessels, nerve fibers and also lymphatic follicles. Bottom layer of the epithelium, the stratum basale is where cell divisions are frequent. |
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Tongue filiform and fungiform papilla - He
Slides shows keratinization on top of filiform papillae. This makes our tongue look white. The keratinizing is often loosely fixed to the tip of the papilla. This is not stratified squamous keratinizing epithelium, but non-keratinizing epithelium with light keratinization in some spots. |
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What the difference between a newborn and adult tongue? |
In newborns the tongue is pink due to the cornification of the filiform papilla is not yet visible. In adults the tongue has a white appearance due to the keratinizing on the top of the filiform papillae. |
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What are zymogen granules and in which slides are they visible? |
Visible in submandibular slides sometimes. Granules are found in many exocrine secretory cells. They contain the precursors of enzymes that become active after the granules leave the cells. Zymogen - means proenzyme, a inactive precursor of a enzyme |
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A papilla fungiform surrounded by filiform papillae The papilla fungiform is infiltrated by lymphocytes |
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Circumvallate papilla - He This slide is from the tongue. Papilla circumvallate - Largest type - Arranged in a V-shaped line on the border of the body and the root of the tongue. - Lie anterior to the terminal sulcus -We have 9 - 11, with 2-3 mm diameter - Surrounded by a circular sulcus - Contains numerous taste buds on lateral aspect - The trench is kept clear by watery secretum of the serous glands opening into them -> Ebners glands. We also find mixed salivary in this region. Taste buds - Has sensory epithelial cells = neuroepithelial cells - Sensory cells are secondary Foliate papilla are leaf-shaped, and found posteriorly on the side of the tongue, infront of the circumvallate papillae. These papillae are not specific for humans, may have a few. Contain numerous taste buds on their lateral sides. |
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Porus 1. Receptors cells 2. Basal cells - Zone of proliferation 3. Sustentacular cells 4. Nerve fibers |
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What's the difference between connective tissue papillae and papilla of the tongue? |
Lamina propria sends ct. papillae into the epithelium layer for blood supply. Papilla of the tongue are surface epithelial projections, that give the tongue a velvet look. |
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Lingual tonsils - HE - Slide from root of the tongue Lymphatic follicle is a accumulation of follicles - Must no have a germinative center Secondary lymphatic follicles can be seen with a lighter germinative zone and a darker ring, called mantle or corona. The germinative center, which defines the secondary lymphatic follicles, develops when an lymphocyte which has recognized an antigen returns into a primary follicle and proliferates. The large immature lymphocytes have a more dispersed nuclei, or euchromatin, which makes them lighter. Follicular dendritic cells can also be seen in the germinal center, dispersed between lymphocytes. - Multiple, thin branching cytoplasmic process that interdigate B-lymphocytes - Cell can retain antigen in it´s surface of long periods - Not Antigen presenting cells, because they lack MHC II molecules The presence of a secondary lymphatic follicle tells us that 1. Activation and proliferation of lymphocytes 2. Differentiation of plasma cells 3. Antibody productionThe number of FDC and macrophages will often increase dramatically in response to an antigen Tonsils - Group of lymphatic follicles in a mucous membrane, covered by epithelium - Function of tonsils is local immunological protection of the mucous membrane they belong to MALT -> mucosa associated lymphatic tissue Lingual tonsil - Epithelial layer -> stratified squamous non-keratininzing epithelium - Lymphatic follicles embeded in mucous membrane, in the reticular ct of the lamina propria - B lymphocytes are found in the follicles, T lymphocytes are in between. - In deep layer we find skeletal muscle in 3 perpendicular directions, fat cells, numerous of mixed salivary glands, vessels and nerves The inflammation of the lingual tonsil are very rare vs palatine tonsil because the crypts of this tonsil are not as deep, and doesn't´t contain as many mucous glands. Muscle in this slide appear as 3rd - Sup and inf longitudinal - Vertical muscles - Transverse muscles - Between muscles we find fat cells, mixed salivary, mostly mucous, vessels and nerves. |
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Lingual tonsil - HE In this slide we can see an slightly eosinophilic territory, here the tissue mass consist of desquamated dead epithelial cells. This can be caused by a deep crypt loosing it´s connection to the surface, and the epithelial cells accumulating to form a detritus. |
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Palatine tonsil - HE - belongs to Waldeyer´s ring of tonsils EPI- Stratified squamous non-keratinizing epithelium In lamina propria we find numerous lymphatic follicles - Describe primary and secondary lymph node Function is a part of local immunological portion of the mucous membrane, belonging to MALT. Palatine tonsil have deep crypts. - Crypts play important role in the dangerous diseases -> follicular tonsilitis, since they are a hiding place for bacteria. - Tissue debris and pus will collect in the crypts, and appear as white spots. Framework of the follicles - > reticular connective tissue in lp - in ct high endothelial veins may be present -> cuboidal epithelium. Where the lymphocytes can enter and exit the tonsils. Lymphocyte -free denser ct under the tonsil -> capsule Tonsil does not posses afferent lymphatic vessels, the lymph will drain from the lymphatic tissue of the tonsil via efferent lymph vessels Slide we can also see mixed salivary glands, fewer than lingual, and skeletal muscle in 2 directions. |
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What is a secondary lymphatic follicle? |
Secondary lymphatic follicles can be seen with a lighter germinative zone and a darker ring, called mantle or corona. The germinative center, which defines the secondary lymphatic follicles, develops when an lymphocyte which has recognized an antigen returns into a primary follicle and proliferates. The large immature lymphocytes have a more dispersed nuclei, or euchromatin, which makes them lighter. Follicular dendritic cells can also be seen in the germinal center, dispersed between lymphocytes. - Multiple, thin branching cytoplasmic process that interdigate B-lymphocytes - Cell can retain antigen in it´s surface of long periods - Not Antigen presenting cells, because they lack MHC II molecules The presence of a secondary lymphatic follicle tells us that 1. Activation and proliferation of lymphocytes 2. Differentiation of plasma cells 3. Antibody production The number of FDC and macrophages will often increase dramatically in response to an antigen |
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Definition of
1. Lymphatic follicle 2. Tonsil 3. Lymph node |
1. Lymphatic follicle or nodule is a group of lymphocytes, which not necessailry has germinative center. - inactive lymph nodules without germinative center are primary follicles. - If a follicle does have a germinative center, it still might happen that it doesn't show in the slides, as its cut tangential. 2. Tonsil: Group of lymphatic follicles in a mucous membrane, usually with a hemicapsule 3. Lymph node is a group of regularly arranged lymphatic follicles with capsule, which are connected to the lymph and blood circulation |
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What are the differences between tonsils? |
Palatine tonsil - Stratified squamous non-keratinizing epithelium - Deep crypts - Skeletal muscle in 2 directions - Few salivary glands Lingual tonsil -Stratified squamous non-keratinizing epithelium - Shallower crypts - Skeletal muscle - 3d - Many mixed salivary glands Pharyngeal tonsil -Pseudostratified columnar ciliated epithelium -Skeletal muscle - Salivary glands in some cases Tubarian tonsil -Pseudostratified columnar ciliated epithelium -Elastic cartilage - Skeletal muscle and Salivary glands |
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Immunity is divided into two parts |
Innate or natural - Rapid reaction - Acceleration of immune reaction is linear - Granulocytes, monocytes, macrophages, dendritic cells, NK cells Acquired or specific immunity - Pathogen specific - the immune answer requires more time - Immunological memory will build up, increases the immune reaction exponentially - B-lymphocytes, T-lymphocytes, follicular dendritic cells |
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What is an antigen, and what are antigen presenting cells? |
Antigen is a substance which evokes a immune reaction. Antigen presenters are macrophages, dendritic cells, which capture antigens via phagocytosis, and display them on the outer surface of cell membrane. So they can react with other immune cells. |
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Lymphatic system Lymphatic circulation |
Lymphatic system is the organisms defense system, which can protect the body against pathogens, foreign bodies and tumor cells. Lymphatic circulation is the interstitial fluid which is partially drained via lymphatic vessels to primary lymph nodes, from the primary lymph nodes they are drained to lymphatic vessels and to secondary and tertiary nodes. From here they are collected into great lymphatic vessels and duct, which drain into the venous angle of the larger veins |
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Primary lymphatic organs |
Bone marrow - development of cellular elements in the circulating blood and lymphocyte precursor cell Thymus - Bone marrow derived T-lymphocytes precursor will differentiate into functional T-lymphocytes |
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Secondary lymphatic organs |
Lymphatic follicles, tonsils, lymph nodes, spleen and lymphatic systems associated to the body surface -> SALT and MALT - Mature lymphocytes from bone marrow and thymus will populate the secondary lymphoid organs. |
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How is the internal framework of lymphoid organs? |
The internal framework is based on reticular connective tissue in all except thymus. Reticular fibers are hardly recognizable as the cytoplasm process of reticulum cells migrate over them. Intercellular space of reticular ct are filled with lymphocytes. |
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What is the size of lymphatic follicles? What is the difference between primary and secondary lymphatic follicles? |
Lymphatic follicles are accumulation of lymphatic tissue, cells. - Primary lymphatic follicles: 50-100um - Secondary lymphatic follicles: 200-400 um Primary lymphatic follicles have no germinative center. Secondary lymphatic follicles have a germinative layer, and mantle/cap around. - Germinative center has B-lymphocytes, follicular dentritic cells, T-helper lymphocytes and macrophages |
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Lymph node - HE - drawing Ct framework of reticular ct Has both blood and lymph circulation - Blood and lymph vessels enter (afferent) among the convex border and exit(efferent) at the hilum, or concave border. - B-lymphocytes in the follicles in the cortex - T-lymphocytes int he paracortex Capsule - Dense connective tissue around the node Trabeculae - Dense connective tissue which extends from the apsule into the substance of the node. - Forms a gross framework Reticular tissue - The lymph node is composed of reticular cells and fibers, which form the supporting meshwork throughout the organ - Mesenchymal orgin Reticular cells - Reticular cells -> synthesize and secrete collage, attracts T cells, B cells, etc - Dendritic cells - > Monitor local environment for foreign substances and presents to antigen-specific T cells * found in T-lymphocyte-rich areas - Macrophages -> Both phagocytic and APC - Follicular dendritic cells -> long, thin cytoplasmic processes which surround B-lymphocytes. *Found in germinative centers, and can retain antigens on the surface for a long period of time. *Doesn't have MHC, so they are not APC Medulla 1. Medullary cords - basophilic cords - Consist of B-lymphocytes, dendritic, plasma cells and macrophages 2. Medullary sinus - lighter stained areas - Receive lymph from trabeculae sinus and lymph filtered through cortical tissue Plasma cells - Derived from B-lymphocytes, oval round large cells with eccentric nucleus. Produce immunoglobulins and antibodies Cortex - Cortex is composed of B-lymphocytes containing lymphatic follicles with FDCs and macrophages Paracortex - Highly endothelial veins and T-lymphocytes. Interdigitating dendritic cells that present antigens to the T-lymphocytes HEV -lined by columnar or cuboidal epithelium Most lymphocytes enter the lymph node via high endothelial venules Important role in circulation and concentration, as they transport 35% of fluids and electrolytes out via blood stream Lymph circulation Afferent lymph vessel -> marginal sinus -> cortical sinus -> paracortical sinus -> medullary sinus -> efferent lymph node |
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1. Medulla - Medullary cords and medullary sinuses 2. Paracortex - High endothelial veins and T lymphocytes 3. Cortex - Consist of follicles with B lymphocytes 4. Capsule - Dense collagenous ct on surface 5. Trabeculae - cortical sinus 6. Afferent lymph vessels - Along the convex border 7. Hilum of the lung - Efferent lymph vessels, vein and artery 8. Marginal sinus - Beneath the capsule |
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Show the root of lymph flow |
1. Marginal or subcapsular sinus - Top of the slide, right below capsule- Connection with the afferent lymph vessels 2. Cortical or trabecular sinus 3. Paracortical sinus 4. Medullary sinus 5. Exit via efferent lymph nodes |
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Spleen - HE 1. White pulp -Lymph sheath around the vessels lymphatic follicles 2. Red pulp - Red blood cells - erythrocyte degradation 3. Capsule 4. Trabeculae - Trabculated arteries |
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Spleen follicle - HE 1. Germinative center 2. Mantie zone or 3. Marginal zone 4. Periarterial area of the follicle 5. central arteriole 6. Red pulp 7. Trabeculae |
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Spleen - HE Function is filter the blood stream, and remove old erythrocyte by the spleen. Minimal blood storage capacity, but 1/3 of thrombocytes Blood production during fetal life Has a rich supply of macrophages and dendritic cells allowing it to monitor the blood immunologically. Parts 1. Capsule - Dense ct with some smooth m - In animals this is used since spleen holds large RBC reserve 2. White pulp - lymph sheath around vessels and lymphatic follicles - Central artery - Follicles are local expansions of PALS, displace the artery to an eccentric position 3. Red pulp - Consist of splenic sinuses separated by splenic cords - Splenic cords consist of reticular connective tissue - Large amount of dendritic, macrophages, lymphocytes, plasma cells will reside inside the reticular meshwork of the splenic cords - Extremely long endothelial cells allowing RBC to pass in and out of sinuses. Processes of macrophages will extend into the lumen of sinuses, to monitor blood stream. - RBC and erythrocyte degradation 4. Marginal zone - Found between white and red pulp. - Marginal sinuses, where lymphocytes from blood vessels may exit the blood stream. - Filtration of blood 5. Trabeculeae 6. Hilum - Splenic artery and vein, nerves and lymphatic vessels - Lymphatic vessels originate in the white pulp near trabeculae Blood circulation of spleen 1. Splenic a 2. Trabecular a 3. Central a a. margin a -> white pulp -> marginal sinuses b. penciliform a -> ellipsoid a. 4. Ellipsoid a - either open or closed circulation. Closed circulation 1. Ellipsoid -> directly into sinusoids -> venules -> trabeculated veins Open circulation 1. Ellipsoid -> red pulp -> sinusoids -> venules -> trabecular veins Central artery is ensheathed by T-lymphocytes, called PALS - Periarteriole lymph sheath Ellipsoid a. is a capillary - Sheath is built up from macrophages, plasma cells, reticular cells and reticular fibers. - Function to detect antigens |
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Contains, framework, vessels, cells, layers |
Thymus - HE Primary lymphatic organ Bone marrow derived T lymphocyte precursors will develop in the thymus, and leave via high endothelial venules as mature T lymphocytes Develops through 3 stages - Epithelial thymus - Lymphatic thymus - Adipose thymus Thymus contains T-lymphocytes, dendritic cells, macrophages and epithelium reticulum cells. - Bone marrow derived T-lymphocytes precursors will differentiate into functional mature T-lymphocytes in thymus Capsule - Thin connective tissue Trabeculae - Extend into parenchyme of organ - Contains blood vessels, efferent lymphatic vessels and nerves. Not afferent Thymic lobules - Not true lobules, but made by trabeculae - Cortical caps over continuous inner medullary tissue Thymus slide has no lymphatic follicles or reticular fibers. -cortex and medulla can give the look of a secondary follicle The framework is epithelium reticulum, and is of endodermal origin. -Cells with processes, covered in lamina basalis - Large, pale, oval nuclei - Secrete thymosin, affecting maturation of T cells Cortex - In the thymic cortex we find that it´s darker stained, this is due to the closely packed developing T-lymphocytes or thymocytes -T-lymphocytes occupy the spaces within the epithelioreticular cells Medulla Contains a large amount of epithelioreticular cells and packed T cells. Contains mostly large lymphocytes, giving it lighter staining Hassal bodies is a distinguishable feature of thymic medulla Vessels of the thymus will make loops in the medulla. - In cortex we only find capillaries and post capillary venules. Hassal bodies are concentrically oriented epithelium reticulum cells with keratohyalin granules and cytokeratin filaments Lymphopoeitic stem cells will proliferate in cortex, and during maturation move to medulla. Cells can enter or exit the parenchyma of thymus through the walls of the postcapillary venules. Blood-thymus barrier Protects developing lymphocytes in the thymus from exposure to antigens - capillary endothelial cell + basal lamina *Occasional pericytes - Perivascular connective tissue *Contains macrophages - Basal lamina + epithelial reticulum cell Positive and negative selection - Thymus function 1. Positive selection - cortex Those cells which recognize the own MHC I molecules or MHC II moleucles, if not the cells will die. Those cells that pass the positive selection leave cortex and enter medulla 2. Negative selection Only T cells which can recognize it´s own MHC molecules co expressed with foreign protein fragment antigens Those T cells that react with self-antigen displayed by self-MHC are eliminated. After this the cells will leave the medulla and into blood stream - Autoimmune etc |
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1. Cortex - T- lymphocytes 2. Medulla - May communicate with medulla of neighboring lobules. 3. Hassal´s bodies or corpuscle - Hassal´s bodies are concentrically oriented epithelium reticulum cells with keratohyalin granules and cytokeratin filaments 4. Interlobular connective tissue septa |
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Shows the medulla of the thymus
Lower left quadrant a Hassall's body is visible |
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Two Hassall's bodies Hassall's bodies are concentrically oriented epithelium reticulum cells with keratohyalin gran In the larger one the keratohyalin granules are recognizable |
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Submandibular gland - HE High power 1. Mucous cells 2. Serous cells 3. Intercalated ducts with simple cuboidal epithelium - Eosinophilic cytoplasm |
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Larynx, front cut - HE Part of lower respiratory tract Epithelium changes in the vocal fold from pseudo stratified columnar ciliated epithelium to non-keratinizing epithelium Lp contains numerous mixed salivary glands, except in the region of the vocal fold In some slides we can see epiglottis -> elastic cartilage. In older age the hyalin cartilage may ossify, so we may see the ossification of cartilage with osteocytes in some slides. - bony trabeculae and bone marrow layers 1. Tunica muscosa - Epithelial mucosa *Pseudostratified, except at vocal lig - Lamina propria *mixed salivary glands except in vocal fold 2. Tunica muscularis - Triangular and quadrangular membrane - Thyroid and cricoid -> hyalin - Intrinsic m between cartilages and lumen -> longitudinal thyroarytenoid m and vocalis m cross section - Cricothyroid m 3. Tunica adventitia Pseudostratified ciliated epi - Ciliated - basal bodies - Reserve cells for regeneration - Lymphocytes - Goblet cells Kinocilia 0,2 um in diameter and 5-7um long - 2 microtubules in middle , 9 doublets around - Surrounded by axonem, attached to basal bodies. |
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1. Epi= Pseudostratified columnar ciliated epithelium 2. Serous gland 3. Vestibule 4. Quadrangular membrane 5. Vestibular fold 6. Ventricle 7. Vocal fold - epithelium stratified squamous non-keratinizing 8. Vocal ligament 9. Vocalis muscle 10. Triangular membrane or conus elasticus 11. Subglottic cavity 12. Epithelium= pseudostratified ciliated epi The cartilage we see is the thyroid |
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ventricle of larynx Shows us the difference in where epithelium changes, and what we find in the lamina propria |
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Example of older hyalin cartilage which ossify. Border between ossified and cartilaginous areas |
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Trachea - HE Two parts of the trachea, cartilaginous part and membranes part. Consist of concentric layers of different tissues 1. Tunica mucosa - Pseuodstratified columnar ciliated epithelium *Kinocilia anchored to basal bodies *Goblet cells - Very thick basal membrane - Lamina propria *Upper: Loose ct with elastic fibers and vessels *Lower: more compact ct. with fat cells and salivary. Cartilaginous part - Hyalin cartilage surrounded by perichondrium - Cartilage consist of type II fibers. Looks homogenous because of the refractive index of the ground substance and fibers is the same. - Function is to prevent the trachea from collapsing during breathing. Membranous part - Contains smooth muscle Adventitia - External layer on the outside of the cartilage - Loose c.t. with vessels sitting on the basement membrane 2. Tunica muscularis - Membranous part -> smooth muscle - Cartilaginous part -> hyalin cartilage 3. Tunica adventitia |
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1. Tunica mucosa 2. Tunica submucosa or deep layer of lamina propria 3. Tunica muscularis 4. Tunica adventitia 5. Pseudostratified ciliated epithelium with kinocilia, goblet cells, basal bodies, and thick basement membrane 6 and 7 is lamina propria of tunica mucosa 8. Glands in submucosa or deep layer lp 9. Hyaline cartilage |
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1. Pseudostratifed ciliated epithelium 2. Very thick basal membrane 3. mixed salivary glands 4. Smooth muscle from membranous part 5. Hyalin cartilage from cartilaginous part |
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Lung - He Tunica mucosa 1. Main (principle) bronchi 2. Lobar bronchi 3. Segmental bronchi 4.-11. -> Bronchi 12. Last bronchi or terminal bronchus All above have - pseudostratified ciliated epithelium - cartilage + smooth muscle 13-17. Bronchiole -> simple columnar with kinocilia 18. Terminal bronchiole -> simple columnar ciliated 19-22. Respiratory bronchiole -> simple cuboidal 23. Alveolar duct -> simple squamous - From 13 to 23 we only have smooth muscle Pulmonary lobule - Pyramid shaped territory that belongs to the first bronchiolus of the system. It´s base turns the surface of the lung, and the outlines are seen in gross anatomy as black lines due to dust in lymphatic system Blood-air barrier - Type I pneumocytes - Pulmonary capillary endothelium - The two basements membranes, often fused to one. Alveoli - Lined with pneumocyte I and II - pneumocyte I -> squamous cell, covers 90% - Pneumocyte II -> cuboidal, produces surfactant - Alveolar septa with elastic fibers, reticular fibers, alveolar macrophages, capillaries and smooth muscles cells. |
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1. Bronchus - Small hyaline cartilage in wall 2. Bronchioli - No cartilage 3. Terminal bronchioli - No cartilage 4. Respiratory Bronchioli - No cartilage 5. Alveolar duct - No proper continuous wall 6. Branches of pulmonary artery 7. Cross-section of alveoli belonging to alveolar ducts 8. Hyalin in wall of bronchi |
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Lung - HE 1. Large bronchiolus 2. smaller bronchiolus - Probably cut at level of division 3. Vein, not belonging |
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Staining, circulation, muscles during breathing |
Lung - dog, orcein staining 1. Bronchiole 2. Branch of pulmonary artery Under the epithelium of the respiratory tract we find a strong meshwork of elastic fibers -> Lp Elastic fibers are also in the wall of alveoli. The elastic fibers allow the lungs to expand during inhalation, to take in the maximum volume of air, and therefore more air can be utilized. Lesser and greater circulation of lung Lesser or functional circulation 1. Right ventricle 2. Pulmonary artery - CO2 3. Capillaries - gas exchange 4. Pulmonary veins - O2 5. Left atrium Nutritive circulation 1. Bronchial arteries - thoracic aorta 2. Capillaries 3. Bronchial veins 4. Azygous system Greater circulation or systemic Left atrium -> left ventricle -> capillaries --> right atrium Inspiration - Diaphragm contracts and pulls downwards, while the intercostal muscles contract and pull up. increases size of thoracic cavity, and decreases pressure inside -> air rushes in Expiration - Diaphragm relaxes, volume of thoracic cavity decrease, which increases the intrapleural pressure, and the lungs will contract and air forced out |
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Wall of heart - right atrium - He 3 layers of heart wall 1. Endocardium - right in picture - Lies on the inner surface the heart - Composed of endothelial and sub endothelial layer - Contains Purkinje fibers 2. Myocardium - Contains heart muscle cells - X or Y shaped - Connected via intercalated discs -> Eberth lines - Cross section and longitudinal - Between muscle cells ct is connected to subendothelial and supepicardial ct. - Many blood vessels - Capillaries next to almost every muscle cell 3. Epicardium - left - Visceral pericardium - The outer surface is covered in serosa, mesothelium -> simple squamous epithelium - Beneath mesothelial layer there is loose ct and fat cells. -Larger vessels and nerves embedded here 4. Pericardium - Not shown in slide - inner sufrace lined by mesothelium - Two facing mesothelial layers of peri and epicardium ensure free movement of heart. -Outermost layer of pericardium is dense ct. Valves - Not shown in slide. - The surface of valves are covered by endothelium - Ct between two endothelial layers has spongy and fibrous layer - Dense fibrous layer is continuous with anulus fibrous, and is found on the side exposed tot he most pressure. - Spongy layer contains fibroblast, macrophages, hyaluronic acid, protoglycans and fewer fibers - Valves does not contain blood vessels ANP and BNP is produced by the heart - ANP i s released by the atria, vasodilator and natriuretic effects - BNP released from ventricular heart muscle |
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1. Purkinje fibers 2. Endocardium 3. Myocardium |
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1. Lipofuscin pigment Since muscle cells are long-lived cells they may contain lipofuscin pigments. Brown color Lipofuscins granules are secondary lysosomes, which contain indigestible substances. May contain carbohydrates fats, membrane fragments, metallic ions 2. Intercalated discs or Eberths lines |
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What are the typical layers of tube shaped organs? |
1. Tunica mucosa - Epithelium mucosa - Lamina propria mucosa -> loose ct - Lamina muscularis mucosae -> thin layer of sm 2. Tunica submucosa - Loose ct with blood vessels, plexus submucosus and often glands 3. Tunica muscularis - Smooth muscle - Almost always inner circular outer longitudinal - Between muscular layers the myenteric plexus - except urinary system 4. Tunica adventitia - loose ct or in organs covered by serous membrane 4. Tunica subserosa -> loose ct 5. Tunica serosa -> mesothelial cell layers - Simple squamous epithelium |
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Esophagus - HE Cross-section -inner layer will of Tm will be cut longitudinal, outer will be cut circular. 1. Tunica muscularis 2. Tunica adventitia 3. Tunica submucosa 4. Muscularis mucosae 5. Epithelium mucosae 6. Lamina propria Layers Tunica mucosa (4,5,6) - Epithelium mucosa -> stratified squamous non keratinizing (5) *Ct papillae -Lamina propria mucosae (6) *Loose ct, vessels, mucous/cardiac glands, lymphatic follicles - Lamina muscularis mucosae (4) *Layer characteristic forgi. Thin layer of longitudinal sm. Tunica submucosa 3 - Loose ct with blood vessels and mixed salivary - Contain plexus submucosus, Meissner plexus - Regulates mucosa, submucosa and glands Tunica muscularis 1 - Smooth muscle - Based on appearance you can tell cross or long - Inner circular, outer longitudinal - Myenteric plexus between layers * Auerbach´s plexus, regulates smooth m Tunica adventita 2 - Loose ct |
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Esophagus - HE Cross-section - Inner m is cut longitudinal, outer m is cut circular Lamina propria is loose ct Border between lp and sm we can see smooth muscle bundles Two layers of tunica muscularis Tunica adventitia in right corner Ct papillae must not be mixed with ducts of glands |
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Esophagus and vagina is often mixed. What´s the difference in 1. cytoplasm of epi 2. Ct papillae 3. Lamina muscularis 4. Glands 5. Tunica muscularis |
Esophagus 1. Light eosinophilic in esophagus 2. Present 3. Longitudinal smooth muscle 4. sometimes present 5. Inner circular and outer longitudinal Vagina 1. Very pale eosinophil 2. Present 3. Absent 4. Absent 5. Meshwork of smooth muscle |
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Cardia HE Transition between esophagus and stomach Layers Tunica mucosa 1. Epi - Simple columnar epithelium - secretory surface, mucous containing columnar cells, not goblet cells - Secretion is continuous and protective function 2. Lamina propria mucosae - Cardiac glands - mucous glands *tubular, branched, coiled - Between the the epithelium and muscularis mucosa 3. Lamina muscularis mucosae - smooth muscle in longitudinal Tunica submucosa Vessels, glands are not typical in submucosa of stomach. Tunica muscularis Inner layer in cross-section and outer layer in longitudinal section Tunica serosa Mesothelial cell layer - Simple squamous epithelium Visceral layer of peritoneum Transition between the stratified squamous non-keratininzing epithelium of the esophagus and the simple columnar epithelium of cardia Gastric pits are lined with surface epithelium and are relatively deep Mucous is secreted to prevent that HCl and enzymes enter esophagus Mucos contains - Mucins -> barrier for pepsin - Bicarbonate -> buffer against HCl - Phospholipids With PAS-H staining the epithelium of the cardia is stained very deep purple because the mucous containing columnar cells are PAS positive. The epi of the esophagus also get a deeper color in the pianocellular cells, due to their glycogen content |
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1. Transitional zone 2. Stratified squamous non-keratinizing epithelium of esophagus 3. Simple columnar epithelium of cardia - With secreting epithelium 4. Lymphatic tissue 6. Gastric pit |
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Fondus or body of stomach - HE No vili in stomach 1. Tunica mucosa Epi -> Simple columnar with secreting surface - All epi cells secrete mucigen. b/c of this they do not stain well with He -> paler area - No microvili or goblet cells Lamina propria (1) - Lamina propria forms core of the folds - Gastric pits are small depressions into the lamina propria 1/3 - Gastric glands are found in lower 2/3 of mucosa, and open into the gastric pits - Simple tubular and branched Lamina muscularis mucosa (2) 2. Tunica submucosa (3) - May see nerve cells 3. Tunica muscularis (4) Circular inner Longitudinal outer Oblique parts May see nerve cells between the layers of tunica muscularis 4. Tunica serosa - Intra peritoneal We also find additional cells in gastric pit 1. Undifferentiated cells - in neck - Small in number - Reserve cell 2. Mucous neck cells - Mucous secreting cells -Small and light cells - Secrete mucigen during digestion 3. Parietal cells - corpus of gastric pits - Large eosinophilic cells with round nucleus - Stained eosinophilic because large amounts of mitochondria - Secrete HCl and intrinsic factor - Intrinsic factor needed for B12 absorption - Stimulated by gastrin, Ach, histamin 4. Chief cells - Fundus - Exocrine - Basal part of the glands - Secrete pepsinogen - secrete protein, rough ER is needed -> stain basophilic 5. Enteroendocrine cells - Small clear cells in epithelium - Secrete hormones -> Gastrin, histamin, somatostatin, prostaglandin, secretin PGE3 |
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1. Chief cells - Exocrine - Secrete protein, pepsinogen - Basophil b/c of ER - Basal part of gland 2. Parietal cells - in middle third of mucosa - Large eosinophilic cells with round nucleus - Secrete HCl and instrinsic factor - Instrinsic factor is a glycoprotein which is needed for B12 absorption. B12 is needed for RBC - Can be stimulated by gastrin, histamine, vagus - Since parietal cells pump H+ against concentration they have large amounts of mitochondria. This stains them eosinophilic because large amounts of mitochondria. |
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Fondus or body of stomach - PAS-H With this staining we can see the mucous in the surface cells and the mucous wedging between the parietal cells in the proximal portion of the glands as deep purple. We can also see the basement emmbrane Only top portion of lamina propria are PAS-positive - Mucous neck cells |
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Pyloric part of stomach - HE Folds are created from lp surrounded by epithelium mucosa. - No vili in stomach We find glands in the lamina propria, lower 1/3. Contains only/mostly mucous cells -Coiled tubular, many cross-sections The gastric pits are wider and deeper, occupying 2/3 of mucosa. 1. Tunica mucosa -Epithelium -Lamina propria *Lower part of lp, coiled tubular mucous glands. *No parietal or chief cells - Muscularis mucosa *Found below the glands, deeper than normal 2. Tunica submucosa 3. Tunica muscularis - Circled muscular layer of tunica muscularis will be thickened if the slide is from the region of the pyloric sphincter 4. Tunica serosa |
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Pyloric part of stomach - HE 1. Mucosa muscularis - Found beneath the glands 2. Glands -Lower part of lp - Contain mucous glands - Tubular coiled - Gives pale staining 3. Lamina propria 4. Gastric pits |
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Pyloric part of stomach stained with HE |
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Pyloric part of stomach - PAS- H In this slide we can see the imaginary border between the pits and glands Mucous surface cells and the mucous cells in glands stain deep purple Whole lamina propria is filled with PAS-H positive mucous cells Mucous secretion protects the duodenum against gastric acids and enzymes |
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How to distinguish the parts of the intestinal system? 1. Villi and glands 2. If only glands |
1. Examine the whether there are villi and glands - If there is glands, it can be both the stomach and crypts of small intestine. -If there is both villi and crypts than it´s always the small intestine. -Check the submucosa for *Brunner´s gland -> duodenum *Nothing special -> jejunum *Aggregated lymphatic follicles -> Ileum 2. If only glands then it has to be stomach or large intestine. - In stomach the deeper part of of mucosa tubular glands are seen with typical cells opening into gastric pits - In large intestine we see tubular glands with abundant of goblet cells, often in cross-section |
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Duodenum - He Has vili, but tip is missing -> not fresh tissue No fold, no protrusions of submucosa 1. lamina propria 2. Muscularis mucosae 3. Crypts - Found above muscularis mucosae 4. Lymphatic infiltraion -Found in certain regions of lp as basophilic regions. 5. Brunners glands - Specific for duodenum 6. Tunica submucosa -Includes Brunners glands - Has vessels 7. Tunica muscularis Layers of duodenum Tunica mucosa 1. Epithelium mucosa - Simple columnar epithelium with striated border - Absorptive epithelium - Goblet cells -Microvili -> fingerlike projection on apical surface, actin filaments. Function to increase surface e area - Microvilli are covered in glycocalix -> PAS-positive 2. Lamina propria mucosa -Intestinal vili are protrusions of lp - Between vili the crypts of lieberkuhn will invaginate lp. -> simple tubular glands 3. Lamina muscularis mucosae - Shown as thin eosinophilic layer Tunica submucosa - Vessel and Brunner´s glands - Glands provide alkaline conditions, which active digestive enzymes. - Open into the crypts, secretes HCO3, neutralizing gastric acid. - Plexus submucosus Tunica muscularis - Inner circular, outer longitudinal - Between layers we can see myenteric plexus Tunica serosa/adventitia - Adventitia or subserosa and serosa can be seen on the external surface. Deepening on which part of the duodenum Crypts of Lieberkuhn cell types 1. Columnar cells - thigth junctions 2. Paneth cells - Bright eosinophilic staining - Contains zymogen granules with antibacterial - Granules on apical side - Secrete gastrointestinal hormones 3. Goblet cells -> mucous 4. Proliferating reserve cells - undifferentiated cells - pluripotent - Replace all types of epithelial cells - High mitotic activity 5. Enteroendocrine cells - granules on basal side - Secrete gastrin, VIP, Secretin, CCK |
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Cell types in crypts of Lieberkuhn |
1. Columnar cells - thigth junctions 2. Paneth cells - Bright eosinophilic staining- Contains zymogen granules with antibacterial - Granules on apical side- Secrete gastrointestinal hormones 3. Goblet cells -> mucous 4. Proliferating reserve cells- undifferentiated cells - pluripotent- Replace all types of epithelial cells- High mitotic activity 5. Enteroendocrine cells- granules on basal side- Secrete gastrin, VIP, Secretin, CCK |
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Duodenum HE 1. Lamina propria - Fills the intestinal vili - Has the crypts of lieberkuhn 2. Crypts of lieberkuhn 3, Muscularis mucosa 4. Brunner´s glands |
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From left to right Crypts 1. Columnar cells2. Eosinophilic paneth cells3. Goblet cell muscularis mucosae Sub mucosa We also have reserve cells and enteroendocrine cells in the crypts |
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Intestinal vili Nothing around something Photo shows any part of small intestine, with closely packed villi. - They have lp core, surrounded by columnar cells with microvili and around the cells is the white gap, which is the lumen. Folds would be seen as something around nothing |
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Jejunum longitudinal cut - HE 1. Circular fold of kerking - Made by submucosa 2. Tunica muscularis 3. Border shows the base of the glands, reaching the lamina muscularis - Intestinal glands -> Crypts of Lieberkuhn 4. Border between vili and crypts Tunica mucosa Epithelium - Simple columnar epithelium with striated border - Goblet cells - Microvilli will increase surface area for absorption Lamina propria - Intestinal vili -> protrusions of LP - Core of vili is ct of lp. Core contains central lacteal. *Central lacteal is divided opened dead-end tube -> lymph capillary - Intestinal glands, crypts of Lieberkuhn *Simple tubular gland *$ different cells, reach the mm Lamina muscularis mucosa -Base of the glands reach this layer Tunica submucosa - Loose ct with vessels and few lymphatic follicles - Circular fold of Kerking * Made by submucosa - collage + elastic fibers Tunica muscularis - Inner circular, outer longitudinal muscle layers Tunica serosa Subserosa and serosa |
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What are structures which increase the surface area for absorption? |
1. Folds - Core: submucosa - Length: 1cm - Surface increases factor of 0.3x 2. Villi - Core: lamina propria - Length: 1mm - Surface increasing factor of 5x 3. Microvili - Core: cytoplasm of cell - Length 1um - Surface increasing factor -> 30x |
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Jejunum - HE 1. Central lacteal 2. Goblet cell 3. Columnar epithelium with striated border - Microvilli 4. Lymphocytes 5. Endothelial cells |
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Ileum - Cross section - HE Lymphatic organ of the small intestine 1.Border between crypts and villi 2. Lamina muscularis mucosae 3. Tunica submucosa 4. Tunica muscularis - inner circular 5. Tunica muscularis - outer circular 6. Aggregated Lymphatic follicles - Peyer´s patches 7. Dome area. Outburst of lymphatic tissue through the lamina muscularis mucosae. Here we find no glands in the lamina propria Tunica mucosa Epithelium - Simple columnar epithelium with striated border - Microvilli and goblet cell Lamina propria - Intestinal vili -> protrusions of the lamina propria - Intestinal glands -> glands of Lieberkuhn Lamina mucosa muscalaris - Found beneath the base of the intestinal glands Tunica submucosa - Groups of lymphatic follicles on the antimesenterial edge of the intestine - Peyer´s patches -Invade the lamina propria and turn connective tissue into reticular connective tissue - In these regions the surface resopritve columnar epithelium changes above -> M- cells with larger and fewer microvilli than regular the regular enterocytes are found scattered Tunica muscularis Inner circular muscle layer will appear in longitudinal cut Outer longitudinal layer in cross-section Tunica serosa We can see nerve cells of the myenteric plexus and serosa |
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Ileum - HE Submucosa invaded in lymphatic tissue |
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Large intestine HE Cecum, ascending, transverse, descending, sigmoid, rectum Circular fold of kerking made by submucosa No vili in the large intestine! 1. Semilunar folds of submucosa 2. Lamina propria 3. Crypts of Lieberkuhn 4. Inner circular muscle 5. Outer longitudinal muscle layer 6. Lamina muscularis mucosae - Separates the glands and the submucosa Tunica mucosa 1. Epithelium - Simple columnar epithelium with microvilli and goblet cells - Colonocytes for absorption of Na+ and water - Goblet cells produce mucous 2. Lamina propria - No villi! - Entire width is packed with crypts of Lieberkuhn - Simple tubular glands containing mostly goblet cells - Very few enteroendocrine cells secreting hormones - NO paneth cells 3. Lamina muscularis mucosae - Separates the lamina propria from the submucosa - Longitudinal smooth muscle Tunica submucosa - Semilunar folds of submucosa, when sm thickens - Ganglion-cells in tunica submucosa -> submucosal plexus Tunica muscularis - Consists of inner circular and outer longitudinal - Longitudinal layer is thicker along tenias Tunica serosa/adventitia |
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Large intestine cross-section of crypts of Lieberkuhn Something around nothing Crypts are lined by columnar, mostly goblet and are seperated by cell rich loose ct in lamina propria |
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Processus vermiformis - Appendix - HE Cross-section No vili or fold Diameter of appendix vary - 0.5 cm to 1 cm Amount of lymphatic tissue will vary Aggregates of lymphatic follicles - GALT - Gut assoicated lymphatic tissue Tunica mucosa Epithelium - Simple columnar epithelium with microvili and goblet cells Lamina propria - Crypts of Lieberkuhn Lamina muscularis mucosae - Found beneath the crypts Tunica submucosa Lymphocytes from the lymphatic follicles are in the submucosae, these will infiltrate the tunica mucosa Tunica muscularis Inner circular, and outer longitudinal The tenias of the colon will unite where the appendix is attached to the cecum, because of this the outer longitudinal layer will be uniformly thicker. Tunica serosa |
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Rectum fetus - He 1. Intestinal part Upper thinner part of the rectum. - Identical to the large intestine -> crypts in lp, submucosa, muscular layer, tunica adventitia 2.Anal part - Anal canal - 4 cm Made up of three zones 3. Columnar zone Made up of Anal columns - stratified squamous non-keratininzing epithelium in fetus, simple columnar in adults - Folds, like islands into the lumen Anal sinuses - Simple columnar epithelium with microvilli - Depression between the anal columns Pectinate line - Wavey line at the level of the anal valves 4. Hemorrhoidal zone - Covered by stratified squamous non-keratininzing epithelium - In the zone of lamina propria and submucosa wide veins can be seen in adult -> due to standing-sitting life style and holding stool - Lots of sensory nerve endings 5. Cutaneous zone - Covered in stratified sqaumous kertaninzing epithelium - At the anus this continues into the external skin - Can contain hair follicles, sebaceous glands, sweat glands, modified sweat glands Sphincter muscles 1. Sphincter ani internus - Smooth m - Continuation of the inner circular muscle layer 2. Sphincter ani externus m - Skeletal muscle - Developing, therefore immature skeletal muscles in fetus slide - Surrounded by smooth muscles cells which comes from outer longitudinal muscle. - Outer longitudinal muscle will split into fibro-muscular strands, which go around the external anal sphincter |
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Rectum fetus - HE 1. External anal sphincter - Skeletal muscle - Surrounded by fibro-muscular strands from outer longitudinal muscle layer - Often developing 2. Internal anal sphincter muscle - Smooth muscle - Continuation of inner circular muscle layer 3. inner circular muscle layer 4. Hemorrhoidal zone 5. Cutaneous zone 6. Columnar zone |
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Plexus myentericus - NADPH reaction Seen similar nerve cells in vegetative ggl, with AgNO3 impregnation. Myenteric plexus or Auerbach´s plexus provides motor innervation to both the layers of the tunica muscularis of the gut. It has both sympathetic and parasympatehetic input It controls the motility of the GI tract -> peristalsis Myenteric plexus originates in the medulla oblongata as a collection of neurons from the central part of the brain stem. Vagus nerve carriers the axons to their destination in the GI tract It´s a segment of the enteric nervous system Staining NADPH - nicotin adenine dinucelotide phosphate - Substrate of a formalin resistant enzyme produced by nerve cells and transported in their axons. - Enzyme is NADPH diaphorase, and during the reaction an election is transferred to nitroblue tetrazolium and gives a blue end product - Reaction was done in whole rabbit bowel - Tunica mucous was removed - Preparation shows the myenteric plexus between the two layers of tuncia muscularis. - Meshwork of nerve fibers, with vegetative ganglion cells at junctions |
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Describe the vessels carrying blood to liver and characteristics of blood in these vessels? How does this blood arrive to the edge of the lobules? |
Portal vein carrying nutrients and hepatic artery carrying oxygen enters the porta hepatis - These divide first into two large branches, and then multiple divisions follows. - Reach hepatic lobules with the interlobular artery and vein. - Both gives of a circumlobular branch, which runs around the lobule |
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After the blood has arrived at the lobules, where does if flow next? |
Both interlobular artery and vein will open into the hepatic sinuses or intralobular veins. In the sinuses the blood from the two systems will mix. These sinusoids are bordered by the row of hepatocytes. Sinusoids have - fenestrated endothels - No basal membrane - reticular fibers - Kupfer cels |
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Where does the blood drain from the lobule? What vessels drive the blood from the liver? |
From the lobule, the blood is drained through the central veins. - Into the sublobular veins - Which in turn unite to larger veins, finally forming the hepatic veins - Hepatic veins will open directly into the inferior vena cava |
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What are the main functions of the liver? |
Processes the nutrients absorbed in the instestine, which arrive via the portal vein Remnant of RBC added to the portal vein via splenic vein Produces bile, which is excreted via the gallbladder in the intestinal tract Synthesize different essential proteins and enzymes that enter the blood stream |
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Where is bile produced, how does it leave, and where does it flow? |
Bile is produced in the liver, by hepatocytes. Bile ducts will travel parallel with vessels, but in opposite direction. Making larger and larger ducts, and appearing at the porta hepatic as hepatic duct. intrahepatic bile ducts The billary tree is lined by simple cuboidal or columnar epithelial cells - Cholangiocytes which monitor the bile flow and regulates content Bile capillaries -> Canals of Hering - > intralobular bile ducts -> interlobular bile ducts -> bigger interlobular ducts -> lobar ducts -> Right and left hepatic ducts Extrahepatic bile ducts Common hepatic duct + cystic duct -> common bile duct |
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What are the structures of the porta triad?
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Interlobular vein, interlobular artery, bile duct |
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Liver of pig - Azan - not given on exam 1. Central vein 2. Porta triad 3. Connective tissue septa dividing the lobules. Use the pork liver to show the structure of the liver, as it has hexagonal lobules which are outlined by thin ct. septa. Hepatic lobule - Hexagonal shape Central vein Cell cords - Actually plates - Consist of hepatocytes lined in single rows areound the central vein - Between cell cords we can find the hepatic sinuses, which are lined by endothelial cells covering hepatocytes. - Hepatocytes are held together by a meshwork of reticular fibers. Portal triad - Interlobular vein - interlobular artery - Bile duct |
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Human liver - Azan 1. Central vein 2. Porta triad 3. Interlobular vein 4. interlobular artery 5. BIle duct - Cuboidal epithelium Sinusoids - Lined by endothelial cells - Opens into central vein - Can contain blood cells, Kupfer cells *Kupfer cells are macrophages which belong to the mononuclear phagocytic system Cell cords of hepatocytes Wall of the central vein is not continuously because the sinusoids are opening into it. Since the interlobular ct is almost totally absent in human, the borders of the lobules are marked only by portal triads, and circumlobar veins around. Fine vacuolication is created by the glycogen storage in hepatocytes Space of disse - Between endothelial lining and the hepatocytes with their microvilli - Contains ito cells/stellate cells, which stores fat and fat soluble vitamins. * Also produce ct fibers of the liver, especially during regeneration Liver cell have apical bordering ( bile capillaries ) and basolateral surface, direction of sinsoids. Thigh junctions will seal the bile capillaries, and separate them from the basolateral surface. Fenestrated endothelial cells of liver do not have basement membrane |
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Liver - He 1. Portal traid 2. Sublobular vein - Continuous endothelial lining, no sinus opening into |
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Portal triad Right -> interlobular vein Top left -> bile duct - Cuboidal epithelium below bile duct the interlobular artery |
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Human liver - He 1. Sublobular vein 2. Central vein |
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Rat liver injected with indian ink + HE This was injected via the portal vein of a rat, therefore only ink in veins. Radially oriented cell cords of the liver are separated by the ink filled sinuses, which point towards the central vein. Interlobular vein, circumlobular vein, sublobular vein, central vein, capillaries Sinusoids and central vein is black, hepatocytes are purple |
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Bile capillaries of frog liver with golgi impregnation Preparation made from frog liver, by golgi impregnation, or silver Black thin lines are bile capillaries filled with silver - Made by the delicate groove system of the neighboring liver cells - Yellow is the liver cell cords White is empty space -> sinusoids Black spots are grains of a specifically precipitated silver |
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Gallbladder - HE Function of the gallbladder is absorption of water, concentrating the bile - Removes 90% of water Tunica mucosa - very folded with microvili 1. Epithelium mucosae - Simple columnar epithelium with microvili 2. Lamina propria - Loose ct Deep pouches or Rokitansky-Ashoff sinus - Communicate with the surface in a plane different of our side. Due to the extra wrinkled mucosa, these circular epithelium lined structures are very common. They can extend into the muscular layer no muscular mucosae layer Tunica muscularis - interwoven layer of smooth muscle - Well developed - Contraction will reduce volume of gallbladder, pushing bile out the cystic duct Tunica adventitia - Connective tissue Might be a layer of mesothelium, depending on which side of the gallbladder the slide was taken from. |
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Pancreas - HE Pancreas is a lobulated organ, and lobules are separated by ct. septa Cells of the pancreatic acini are basophilic at their bases, and eosinophilic apically. - Serous cells, secrete amylase, lipase, nucleases etc - Primarily inactive forms - Ergastroplasm, area at base, where rER is active - In the middle of many acini an extra cell is sitting-> centroaciner cells *Belong to initial portion of intercalated ducts, which is protruding deeply into the acini Islets of different cells (1) surrounded by exocrine acini are seen. - These are build up from cell cords with sinusoid capillaries between them -> Islets of Lagerhans. They belong to the endocrine part of the pancreas, and contain 3 cell types * Alpha cells -> producing glucagon *Beta cells -> producing insulin *Delta cells -> somatotatin, VIP 2. Is a neuroinsular cell group - Contains ganglionic cells We also find intercalated ducts which drain into intralobular ducts - No striated ducts |
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Acini of pancreas stained with He 1. Centroacinar cell - First cell of the duct system protruding into the acini Due to shrinkage of tissue, the acini are more separated than normal. Basal part of acini is basophilic, luminar is eosinophilic. |
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What are the parts of a nephron? |
Nephron is the functional unit, we found between 1-2 million units. 1. Malpighian corpuscle body - in cortical labyrinth - Glomerulus - Aff/eff arteries and capillaries - Bowman´s capsule 2. Proximal tubule - Proximal convoluted tubule - in cortical labyrinth - Straight thick descending tubule - in medullar ray, may reach down in to the pyramid. 3. Intermediate tubule - Thin descending part - Thin ascending loop - Creates the hairpin loop in the pyramid 4. Distal tubule - Straight thick ascending tubule *Starts in pyramid and goes to the medullary rays - Distal convoluted tubule *Cortical labyrinth 5. Collecting duct Loop of Henle is created from straight thick descending, thin descending, thin ascending and straight thick ascending tubule |
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Malpighian corpuscle - He Round structure with many nuclei -> basophillic 1. Bowman´s capsule - Visceral layer: Podocyte * on surface of the capillaries of the glomerulus *Foot processes enabling ultrafiltration - Parietal layer: Squamous cells *Capsular epithelium - Urinary pole *Connection of the cavity of the Bowman´s capsule to the start of the proximal convoluted tubule -Vascular pole *where capillaries enter 2. Glomerulus capillary loop system - Glomerulus - Glomerular mesangial cells *Equivalent to pericytes * Not only found in the renal corpuscle, also on the outside along the vascular pole -> part of juxtaglomerular apperatus * Have phagocytosis, structural, secretion function - Filtration happens here |
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Kidney - HE Parts of nephron and malphighian corpuscle should be mentioned Filtration layers 1. Podocytes -> long processes etc 2. Basement membrane -> most important filtration layer 3. Endothelium of capillary - fenestrated. Keeps blood cells from passing - Tight junctions Cortex - Cortex corticis - Malpighian bodies + proximal and distal convoluted tubules * upper part of cortex, which is not interrupted by the medullary rays - Cortex - Malpighian bodies, prox, distal convoluted tubules and medullary rays created by the straight tubules Medulla Straight portion of the nephron Cortical lobule - 1/2+1+1/2 Bordered by the interlobular arteries, and in the middle of the cortical lobule see a medullary ray surrounded by cortical labyrinth Cortical labyrinth Between 2 medullary rays Proximal convoluted tubules, with cuboidal cells with microvilli - Also basal striation and eosinophilic Distal convoluted tubule with low cuboidal and pale eosinophilic staining - Basal striation with larger lumen Collecting duct, cells are closer too each other, looks darker.
Macula densa: Small part of the distal tubule at the vascular pole, with large and narrower columnar cells Urinary pole: connection of the cavity of the Bowman´s capsule to the start of the proximal convoluted tubule
Juxtaglomerular complex or apperatus - Consist of macula densa, extraglomerular mesangial cells and juxtaglomerular cells. - juxtaglomerular cels are special myoepithelial cells in the wall of the vas afferens, producing renin.- - Renin, turns AG to AG-I, which can be further converted in lungs, elevating the blood pressure. - Juxtaglomerular complex can regulate the kidney Juxtaglomerular glomeruli - Glomerulus close to the medullary border. It´s efferent arterioles supply the pyramids
Blood supply Arterial: Abdominal aorta -> renal a. -> segmental a (ant and post) -> lobar a. -> interlobar a. -> arcuate a. -> interlobular a. -> afferent arterioles - >g lomerulus -> efferent arterioles From here it depends whether we are in the juxtamedullary or outer cortical renal corpuscles Juxtamedullary -> Vasa recta (follow medullary rays) -> arcuate veins -> interlobar veins -> lobar veins -> segmental veins -> renal vein Outer cortical -> peritubular capillaries -> interlobular vein -> arcuate vein
Peritubular capillaries The tiny blood vessels which run alongside the nephrons allowing for reabsorption and secretion between blood and inner lumen of nephron. Surrounds the proximal and distal tubules, and the loop of Henle, and is known as vasa recta |
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Kidney - He 1. Cortex 2. Medulla 3. Arcuate artery and vein 4. Medullary rays 5. Renal corpuscle |
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Kidney - He This the cortex part of the kidney 1. Cortical labyrinth - Proximal convoluted tubules *Simple cuboidal cells with microvilli, basal striation and strong eosinophilic staining - Distal convoluted tubules *Pale eosinophilic with low cuboidal cells, and basal striation. Large lumen - Collecting tubules * Cells are closer to each other, looks darker 2. Cortical lobule - 1/2 + 1 + 1/2 Bordered by interlobular arteries, hence in the middle we see a medullary ray surrounded by cortical rays |
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Kidney - He 1. Proximal convoluted tubule - Cuboidal cells with brush border, basal striation, and eosinophilic cytoplasm 2. Distal convoluted tubule - Low cuboidal - Pale eosinophilic - Basal striation, have larger lumen 3. Collecting duct - Cells are closer to each other - Darker |
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Papilla of the kidney - HE 1. lesser calyx - Lined by transitional epithelium - Umbrella cells on surface stretch as a narrow eosinophilic layer of the pear-shaped polygonal cell layer 2. Papilla of the kidney |
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Kidney - He 1. Vascular pole -Distal tubule with macula densa cells - Macula densa cells are taller and narrower columnar cells 2. Urinary pole - Connection of the bowman´s capsule and the start of the proximal convoluted tubule |
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Kidney - He 1. Distal convoluted tubule 2. Proximal convoluted tubule 3. Collecting tubule 4. Urinary pole |
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Kidney perfused with indian ink/He Rabbit kidney The kidney is perfused with indian ink, filled through the arterial system. Lumen of vessels is filled with ink 1. Calyx - Y shaped empty gap which is bordered by transitional epithelium on both sides. 2. Transitional epithelium lining the calyx 3. Papilla with the cribriform area - Covered with columnar epithelium - Papillary ducts will open in the cribriform area 4. Glomerular meshwork showns as little black ball 5. Peritubular capillaries - tiny blood vessels which travel together with the nephrons, allowing for reabsorption and secretion between blood and the inner lumen of the nephron. Peritubular capillaries will surround the proximal and distal tubules, and loop of Henle -> vasa recta 6. Medullary rays Peritubular capillaries will originate from vas efferens and it´s longer branches surrounding the loop of Henle will be called vas recta. - Vas recta supplies the Medulla, vasa recta is a branch of the the vas efferens from the juxtamedullary glomeruli Blood supply Renal artery -> interlobar artery (between pyramids) -> arcuate artery (between medulla and cortex) -> interlobular artery -> vas afferent -> glomerulus capillary -> efferent vessel From here it depends whether it´s a Juxtamedullary glomeruli or outer cortical glomeruli. 1. Juxtamedullary glomerulo Vas efferens -> vasa recta -> arcuate vein 2. Outer cortical glomeruli Vas efferens -> peritubular capillary -> interlobular vein -> arcuate vein |
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Ureter - He Mixed with esophagus 1. Epithelium - urothelium - Transitional epithelium *Layers -> basement membrane, stratum basal, intermediate layer with pear-shaped cells and outer layer is umbrella cells with tight junctions. - Accommodates different volumes - Seals 2. Lamina propria - Does not separate from well form the inner muscular layer 3. Tunica muscularis - Inner longitudinal - Outer circular - Opposite of GI tract 4. Tunica adventita - Does not have serous membrane covering it -> retroperitoneal - Loose layer of ct around it |
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Urinary bladder - He Often mixed with stratified squamous non-keratinining Urinary bladder is infraperitoneal, with parts being covered by the serous membrane. It tackles large volume changes due to it's urothelium. 1. Epithelium - transitional epithelium - Basement membrane, stratum basale, pear-shaped, umbrella cells - Umbrella cells has a folded surface and fusiform vesicles, which allow them to expand and give larger volume. - Pear-shaped cells rearrange, no desmosomes. - Sealed because of tight junctions between umbrella cells. - Ion pumps pump out leakage 2. Lamina propria - Loose ct with elastic fibers - Does not seperate from the rougher submucosa 3. Tunica muscularis - Consist of interwoven muscle with smooth muscle bundles running in different directions and separated by thin layers of ct. 4. Subserosa/serosa or adventitia is the outermost layer of the urinary bladder. - mesothelium + thin layer of ct |
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Mark changes in endometrium What are the changes in hormone levels? Characterize the oogenesis What hormones are produced by ovary? Characterize the spinocellular connective tissue What happens to growing follicles that doesn't ovulate? |
Ovarium - monkey - He Follicle = oocyte + follicular epithelium (later + theca Mark stages of endometrium, and the 3 phases - Menstruation, proliferative phase and secretary phase Mark the changes in hormone levels - FSH - follicle stimulating hormone *Increasing levels, but sudden drop right before ovulation, then increases with LH, and decreases with LH. - LH - luteninizing hormone *induces ovulation, and development of corpus luteum *LH surge right before ovulation, day 14 Follicles and development All the follicles are primary oocyte - 46,4n. The primary oocyte are derived from oogonia, which started their first meiotic division, and ceased it during prophase. - Caused by mitosis inhibiting factor - MIF 1st meiotic division ends just before ovulation. Secondary oocyte ovulates and starts 2nd meiosis, but will only end in case of fertilization. Hormones Estrogen is produced by the theca interna and granulosa cells - Theca interna produces androgen, which is converted by granulosa cells to estrogen Estrogen has a negative feedback to FSH, which decreases the FSH levels, and only the most dominant follicles, which are most sensitive to FSH will survive, the others become atretic. High levels of estrogen induce the LH surge via positive feedback AMH - anti-mullerian hormone - produced by granulosa cells after puberty in females in reproductive age - correlates with number of follicles Progesterone - Produced by corpus luteum - Levels rise after ovulation Estrogen -Levels rise before ovulation - Positive feedback on LH Inhibin - inhibits FSH - Levels rise before ovulation Spinocellular connective tissue Stroma = spinocellular or cell rich connective tissue Found in the cortex Contains follicles Theca develops from Stroma Follicles which doesn't ovulate Most follicles will degenerate, as only one follicle can be selected for ovulation. They will then become atretic follicles by apotosis. During degeneration the granulosa cells will become loose and fall into the atrium, cavity will be filled with ct. Membrane basalis thickens -> Membrane vitrea, which will shows as strong eosinophillic |
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Ovarium - He Slide from monkey All follicles have primary oocyte - 46,4n 1. Epithelium - Simple cuboidal epithelium - Line of Farre - insertion of mesovarium 2. Tunica albuginea - Thick ct layer with dense ct 3. Primordial follicle - 30 um - I oocyte - 46, 4n - Single layer of flattened epithelial cells *Pregranulosa cells -> seperated from ct by basement membrane 4. Primary follicle - 60 um - I oocyte - 46, 4n - Single cuboidal epithelium - granulosa cells 5. Secondary follicle/preantral - 120 um - I oocyte - 46, 4n - Several layers of granulosa cells + theca interna and externa 6. Cortex - Contains follicles of different stages - Stroma -> cell rich ct of the ovary *Also called spinocellular, and theca develops from this 7. Frimbriae - Part of uterine tube Not seen here is the tertiary follicle or antral follicle - 1-2 mm - Antrum contains protoeglycans, hyaluronic acids, hormones, cytokines * Nourishes oocyte and granulosa cells - Early or late based on size - Graafian follicle -> only 1 - Largest follicle -> 1-2 cm Theca interna - Flattened epitheloid ells from the ct right next to the basement membrane of granulosa cells - contains blood vessels Theca externa - the ct of the ovarium (stroma) right next to the theca interna. - Cannot be well separated from the rest of the ovarial ct Follicular development 6-7 month Primordial 30 um -> primary follicle 60um ->secondary or preantral 120um -> tertiary or antral 1-2mm -> Graafian 1-2 cm Preantral growth phase: 120 days Tonic growth phase: 65 days Exponential growth: 20 days At the end of the follicular phase the graafian follicle will rupture -> ovulation During ovulation the cumulus oophorus are detached, and the granulosa cells fell apart |
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Ovarium - He 1. Antral follicle 2. Early degenerating follicle 3. Later degenerating follicle 4. Atretic follicle |
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Ovarium - He 1. Cortex and capsule 2. Vessels of medulla 3. Younger yellow body - corpus luteum 4. Older yellow body - corpus luteum Yellow bodies will turn into corpus albicans Yellow bodies - corpus luteum - Big cells, pale cytoplasm, lipid droplets |
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Ovarium with corpus luteum Also the ovarium 1. Fresh corpus luteum 2. Elder corpus luteum 3. Corpus albicans - Regressed form of corpus luteum - Scar tissue 4. Degenerating follicle |
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Ovarium with corpus luteum and corpus albicans - HE Not to forget that this is a slide in a human ovary. LH is responsible for development of corpus luteum, LH decreases after peak New corpus luteum 1. Fibrin 2. Granulosa lutein 3. Theca lutein Function of yellow body is to produce progesterone to maintain the pregnancy. The length of it´s function depends on fertilization 1. If fertilized trophoblast cells will produce hCG (human choriogonadotropin) which causes the corpus luteum to maintain. - Corpus luteum graviditas wil continue ntill placenta takes over progesterone production 2. In case of no fertilization: Coprus luteum menstruations -> corpus luteum degenerates after 10 days - Creates corpus albicans new corpus luteum The cavity of the former folliculus is first filled with fibrin, which is later invaded by fibrocytes. Granulosa-lutein cells are derived from the granulosa cells. They create the inner cullular layer with big cells with pale cytoplas, - Steroid producing cells -> progesterone - Contain lipid droplets -> yellow body Theca lutein cells are outer cell layer, which develops from theca interna. - Cells are small, more basophilic because of their more densly packed nuclei, cytoplasm is pale though. - Produce progesterone and estrogen Theca externa - Forms a capsule which covers it |
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Layers of new corpus luteum? |
1. Fibrin - Fills the cavity of the former follicle - Will be invaded by fibrocytes 2. Granulosa-lutein cells - Inner cellular layer - Big cells with pale cytoplasm - Derived from granulosa cells - Produce progesterone - Contain lipid droplets 3. Theca lutein - Derived from theca interna - More basophilic nuclei, as it's more densely packed - Smaller cells, with pale cytoplasm - Produces progesterone and estrogen 4. Theca externa - Forms a capsule covering it |
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Uterine tube - HE Thin tube with lumen filled with branching folds of mucosa Very good blood supply Layers of uterine tube 1. Tunica mucosa Epithelium -> Simple columnar epithelium with kinocilia - Kinocilia is 0.2 um in diameter, and 4 um long attached to basal bodies - occasional secretory cells without kinocillia -> PEG cells secreting mucous - Mucous section plays a role in nourishing the egg, facilitating sperm movement, capacitation of spermatozoa - The height of epithelial and amount of PEG cells vary with the menstrual cycle and hormones. Lamina propria is rich in blood vessels - During extrauterine pregnancy it's therefore likely for it to happen in the tube. - Can cause huge bleedings -> Very bad 2. Tunica muscularis - Inner circular, outer longitudinal - In slide the cross-section gives us inner circular in longitudinal cut, and outer longitudinal in cross cut 3. Tunica serosa - Covered by periotneum - visceral layer - mesothelium -> simple squamous - Uterine tube is an intraperitoneal organ Epoophron is a embryonic remnant which we can find in some of our slides which have the mesovary. - Contains the epoophron ducts, covered in simple cuboidal epithelium |
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Uterus proliferative phase - He - endometrium -> 2-3 mm Drawing of endometrium of uterus The function of the uterus is to provide optimal circumstances for the implantation of the fertilized ovum. Because of this, it builds up every month, and when it doesn´t meet a fertilized ovum, it breaks down, and starts over in a new cycle. The changes are continuous, but we have two main phases -> Proliferative phase and secretory phase. Estrogen - during proliferative phase Progesterone - during secretory phase Layers of uterus - 3 main layers Perimetrium - outer - Peritoneum covering the uterus with minimal ct beneath it. - Mesothelium - serosa Myometrium - middle - Built from interwoven smooth muscle - No submucosa Endometrium - inner most - 1 2. Stratum basale - Next to myometrium - Does not participate in cyclic changes, - Not discarded during menstruation 3. Functional layer 4. stratum compactum 5. Stratum spongiosum Cavity of the uterus is lined by simple columnar epithelium, some may have kinocilia. Beneath we find lamina propria -> stroma Changes in endometrium during proliferative phase Glands will regenerate from the stratum basale. - Simple or tubular glands - Glands do not secrete during proliferative phase - Epithelium is fort simple columnar, but later turns pseudostratified columnar epithelium Spaces between glands is filled with stroma -> spinocellular ct Spiral arteries will appear in the stroma - Spiral arteries in stratum functional, straight arteries in stratum basale Glands, stroma and spiral a. are hormone sensitive - Proliferate and growth - Glands wil first elongate, then become coily - When hormone levels drop, the spiral arteries will retract |
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Uterus - proliferative or follicular phase - He |
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Uterus - secretory phase - He In secretory phase the mucous thickens, glands will dilate and become irregular. Due to further elongation and dilation the pseudostratification decreases. Stratum functionale will have wide, coiled glands, and basale will have the narrower part of the glands. At the base of the columnar cells, glycogen will accumulate, and in the lumen of the glands secretum of glycoprotein will appear - Necessary to ensure nutrition for the fertilized and newly implanted ovum Spiral arteries can be found in the stroma between the glands. - Sphincter's which contract when hormone levels decreaes Due to high levels of progesterone the stratum compactum becomes very compact, since the stroma cells enlarge and become epithelium like. - Process called decidualization, since the cells become pseudodecidual cells. - Call them true decidual cells only during pregnant uterus -> provides nutrition for blastocytes If the ovum is not fertilized the endometrium will break down and the menstruation will begin. Hormones produced by trophoblast cells, hCG, would be essential for further changes for the pregnant uterine mucosa |
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Uterus in secretory phase - He We can only see the upper part, but we see the pseudodecidual cells in the stratum compactum caused by the decidualization of the stroma cells Large, rounded, very epithelial-like cells which are in close contact to each other. |
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Cervic uteri - HE Two epitheliums 1. Glandular columnar epithelium - Occasional ciliated cells - Cells tend to overlap - Found above the transformation zone or squamocolumnar junction - Same areas we find cervix glands where we can see that the epithelium is folded, and dipped into areas forming elongated clefts -> cervical glands 2. Stratified squamous non-keratininzing epithelium - Continuous with the epithelium of the fornix of vagina Position of squamocolumnar junction changes with age - puberty it's almost at the exit of the endocervical canal - reproductive age it´s outside the channel, on the exocervic - Menopausal causes it to be further up the endocervical canal Uterine neck is an elongated fibromuscular portion of the uterus - 2-3cm Epithelium of the exocervic is continuous with the mucosa of the vaginal fornices. In the cytoplasm of the endocervical epithelium we find that glycogen accumolates, depending on estrogen influence. - Nuclei of these cells are small, round and regular pyenotic * Large would refer to HPV - The endocervical epithelium changes minimal during menstrual cycle - Due to influence of progesterone and estrogen mid cycle the mucous will become less viscous and alkaline, helping sperm penetrate easier. - Cervical mucosa will prevent ascending infections Stroma of the cervix Fibroelastic tissue - collage + elastic fibers - with a few strands of smooth muscle. Contains many vessels and nerve fibers - Undergoes changes -> collagen fibers decrease, mucopolysacharides increase in ground substance -> causes the cervix to soften/become looser and allow dilation during paturation |
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Vagina - He Stratified squamous non-keratininizing 1. Stratum basal 2. Stratum spinosum 3. Stratum planocellulare The mucous is kept moist be the cervical glands, transsudation, Bartholin gland, lactic acid. Tunica mucosa - Epithelium - stratified squamous non-keratinizing epithelium - Lamina propria - loose ct, with elastic fibers with vessels, nerves and lymphatic follicles. * NO GLANDS No tunica submucosa Tunica muscularis - Inner circular muscle layer - Outer longitudinal layer - Two layers are not separated from each other or from the fibromuscular ct =Meshwork of smooth muscle The pale staining of epithelium is caused by it's richness of glycogen. This is fermented by lactic acid-forming bacteria, keeping the pH in the vagina acidic - pH -> 3.8-4,5 PAP test -> shed of cells from the vagina can eb stained to tell us abount infections |
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Non-lactating mammary gland He In this stage before pregnancy and after breast feeding TDLU - Temrinal duct lobar unit - At the end of the terminal ducts - lobules - Contain progenitor cells that develop acini of lactating gland which can produce milk -Cancer can develop here - The interolbular ct is rich in fat cells and fibers and contains receptors for estrogen and progesterone. 1. Fat cells 2. non-functioning glands/acini in small groups 3. Dense connective tissue 4. Ducts 5. Loose ct |
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Mammary gland during lactation - He Located in the subcutis Mammary gland is a wide lumend apocrine gland. It's a compound tuboalveolar gland, a further modification of the apocrine sweat gland Lobes are separated by a fatty connective tissue Epithelium of the lactating gland will vary in hight Apocrine secretion of fat, and merocrine secretion of proteins Cytoplasm of the cells is pale due to fat and glycogen storage Ducts arelined with cuboidal or columnar epithelium - They are surrounded by myoepithelial cells, which form a definitive layer around the larger ducts. - Contract to eject the milk There are 15-25 lobes which open with the lobar lactiferous ducts on the nipple. Hormones Estrogen -> growth of ducts Progesterone -> growth of acini Prolactin -> stimulates milk production Oxytocin -> milk ejection Milk contains everything important - 88% water, 4% fat, 1% protein, 7% carbohydrate |
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Parietal decidua - pregnant uterus - He Layers of uterus wall Endometrium 1-2. Stratum functionale 1. Stratum compactum - with decidua cells - Epithelial cells which have a accumulation of glycogen and lipids - Provides nutrition for blastocyst implantation 2. Stratum spongiosum - With glands - Remnant of the uterine glands - Lined by flattened cells or cuboidal epithelium - Large lumen 3. Stratum basale - Very thin - Narrowed lumen stratum basale glands Myometrium Perimetrium 3 parts of devidua 1. Decidua parietalis - A parietal layer of the decidua covering the surface of the uterine cavity, but no the embryo 2. Decidua capsularis - Found covering the capsule of the embryo, will be on the side facing the opposite wall with decidua parietalis and uterine cavity 3. Decidua basalis - Portion lying under the implanted ovum and chorion Fertilization human chorionic gonadotropin is secreted by trophoblast cells in the embryo, this causes the corpus luteum to survive, which increases progesterone production, causing the endometrium to further increase. Parts of embryo 1. Chorion laeve - Smooth - Faces decidua capsularis 2. Chorion frondosum - Villi - Faces decidua basalis Decidua basalis and chorion frondosum will fuse creating the placenta, this happens first when the decidua parietalis, chroion laeve and amnion fuse |
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Umbillical cord He Wharton´s jelly - 95% water, hyaluronic acid and GAG The surface of the umbilical cord is covered in simple cuboidal epithelium, which si continues with amnion on the body surface of the fetus Due to it's high water content, it will evaporate quickly after birth, which prevents infection Structures two umbilical arteries - Muscular - Contain deoxygenated blood One umbilical vein - Contains more smooth muscle than normal veins - Can't separate the tunica emdia from tunica adventita due to the smooth muscle in both layers - Contains oxygenated blood Remnant of allantois - Small duct lined with cuboidal epithelium Remnant of omphaloenteric duct |
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Placenta - 1st trimester As pregnancy proceeds certain layers will disappear or become thin, so they are hard to recognize. Maternal part: Decidua basalis Fetal part: Chorionic plate+chorionic vili Following layers build up the placenta 1. Myometrium 2. Stratum basale - very thin, 3. Remnant of maternal glands (1) - Wide lumina, best seen in early placenta 4. Decidua basalis (2) 5. Fibrin (3) 6. Cytotrophoblast cells (4) These above are flat layers, the next layers are more random 7. Anchoring vili (4?) 8. Intervillous spaces (5) filled with maternal blood. - In this space we see cross-section of chorionic villi and placental septa - placental septa are like if the decidua-fibrin-cytotrophoblast layers flexed, appear along the chorionic villi as very eosinophillic - Syncytial knot are from old cells 9. Chorionic plate -Uniform plate with syncytiotrophoblast, cytotrophoblast, chorionic mesoderm. It's covered by amnion Extravillous trophoblast cells - Grow from placenta and penetrate the decidualized uterus - Attaches the placenta to the mother and alter the vasculature in uterus to allow the blood supply for the growing Cotyledon 15-20 - stretches from one placental septum to the next placental septum, within a villi is found Early vs late villi Early villi during 1st trimester will have these layers - Syntitiotrophoblast - Cytotrophoblast - Mesoderm - Endothelia and basement membrane Late villi - Syntitiotrophoblast - Endothelia with basement membrane The thickness of the basement membrane will decrease, and the surface area will increase - Cytotrophoblast will disappear from the terminal villi - More direct connection, makes for a more effective exchange - Trophoblast cells will build up an important immunological barrier |
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What are the types of villi? |
1. Primary villi - only cytotrophoblast - day 11- 13 2. Secondary villi - Extraembryonic mesoderm grows into - Day 16 3. Tertiary vili - Vessels grow inside too |
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Placenta 3rd semester - He 1. Maternal side 2. Chorionic plate The cellular layer gets thinner, the fibrin deposit increases |
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Epididiymis He May find ducts in a tangital section, with no lumen We have two types of tubules 1. Ductus epididymides - Regular, small lumen - Lined with pseudostratified columnar, ciliated epithelium - Thin inner circular and outer longitudinal smooth muscle layer - May find spermatooza inside lumen 2. Efferent ducts of testis - Irregular lumen, since cells which line it are uneven in size - Occasionally they have stereocilia - Ill defined smooth muscle layer around. Sterocilia - 10-15um - Not mobile - Long, tall microvilli with actin filaments - Increase surface, absorption of testicular fluid |
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Epididymis - Azan May find ducts in a tangital section, with no lumenWe have two types of tubules Azan staining the nuclei, cytoplasm, of epi cells and smooth muscle red-pink, the ct fibers become blue Azocarmine and anilinblue 1. Ductus epididymides - Regular, small lumen - Lined with pseudostratified columnar, ciliated epithelium - Thin inner circular and outer longitudinal smooth muscle layer - May find spermatooza inside lumen 2. Efferent ducts of testis - Irregular lumen, since cells which line it are uneven in size - Occasionally they have stereocilia - Ill defined smooth muscle layer around. Sterocilia - 10-15um - Not mobile - Long, tall microvilli with actin filaments - Increase surface, absorption of testicular fluid |
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Testis - He Cell types of spermatogenesis - Stimulated by FSH and starts at puberty 1. Spermatogonia - 46 2n - Found closest to the end the of the seminiferous tubule - Large cells with round nuclei Type A and B spermatogonia - B enter meiosis. 2. Primary spermatocytes - Undergo 1st meiotic division - Located more centrally - Larger cells with rough chromatin structure due to the formation of chromosomes during first maturation division -> 46 4n 3. Secondary spermatocytes - Undergo 2nd meoitic division -> 23 2n - Smaller cells, found more centrally - Only present for few hours -> can not be identified 4. Spermatids - 23n - smaller round cells found in cluster - 6-8um - First most centrally, then they become closely associated with sertoli cells, and are embedded into the cytoplasm - Undergo spermiogenesis -> Spermatozoa 5. Spermatozoa - Found in the lumen - Small, arrowhead shaped cells with long tails Layers of testis Tunica vaginalis - Visceral layer of the peritoenum, thin mesothelial layer on the surface - Simple squamous epithelium Tunica albuginea - Sheath around testis - Dense ct capsule - like tendons - Contains collagen fibers - Inner layer is vascular Septa - The lobules are divided by septa. - Lobules contain seminiferous tubules, lined with special stratified epithelium -> epithelium seminale *seminiferous tubules are surrounded by myoid cells, on the basement membrane - Cells are found in different sizes, mostly with round nuclei - Outer cells sit on the basement lamina Cells of testis Leydig cells - Seen between tubules as scatted - Produce testosterone - Eosinophilic cells, arranged in clusters Sertoli cells - Large nucleus is oval or triangular with prominent nucleus - Makes the blood-testis barrier - Sertoli cells connect to each other via tight junctions - Communciate via GAP junctions - Produce hormones - Phagocytes of cytoplasm |
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Testis - He 1. Spermatogonia - 46 2n - closest to edge - Large cells with round nuclei 2. Primary spermatocyte - 46 4n - Found more centrally - Larger nucleus, rough chromatin structure because of formation of chromosomes - Undergo first maturation division 3. Secondary spermatocyte - 23 2n -Only last for a couple of hours, and can not be identified on slide - Smaller cells, found more centrally - undergo 2nd meoitic division 4. Spermatids 23n - Very small cells found in clusters - found most centrally to the lumen - Closely associated with the sertoli cells, in cytoplasm - Undergo spermiogenesis to become spermatozoa 5. Spermatozoa - Small, arrowhead shaped cells, with long tails hanging into the lumen 6. Leydig cells - Found between the seminiferous tubules, in the interstitial connective tissue - Produce tesosterone - Very eosinophilic 7. Basement lamina - with myoid cells |
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Forniculus spermaticus - Spermatic cord - He Runs from deep inguinal ring to each testis Function is to transport sperm from epididymis to the ejaculatory ducts Structures of spermatic cords 1. Ductus deferens Epithelium -> Pseudostratified columnar epithelium with occasional stereocilia Lamina propria with some elastic fibers Tunica muscularis - Three layer -> inner and outer longitudinal and middle circular Around the ductus deferens medium sized arteries, veins and nerves can be seen. - Wall of vein contains more smooth muscles than normal - Arteries never have smooth muscle bundles in the adventitia! but the veins have smooth muscle in both media and adventita 2. Artery to ductus deferens 3. Testicular artery 4. Pampiniform plexus 5. Testicular nervous plexus 6. Lymph vessels 7. Tunica vaginalis 8. Genital branch of genital femoral nerve And the external surface of the spermatic cord, skeletal muscle fibers from the cremaster muscle can be seens |
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Spermatic cord - He 1. Ductus deferens 2. Pseudostratified columnar epithelium with occaisonal stereocilia 3. Lamina propria with elastic fibers 4. 1st muscular layer, inner longitudinal 5. middle muscular layer, circular 6. 2nd muscular layer, outer longitudinal 7. Small muscular artery |
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Prostate - He 30% of ejaculatory fluid Colliculus seminalis will bulge into the urethra giving it a C-shaped lumen - Where the ejaculatory duct open into the urehtra - The urethra will have either transitional epithelium or stratified columnar epithelium depending on whether the cut was made above or below the colliculus seminalis Ejaculatory ducts can be seen in this slide. - Appear as star-shaped lumen lined with extremely folded mucosa - Pseudostratified columnar epithelium Glands of prostate - Wide irregular lumened apocrine glands - Lined with columnar epithelium - Embedded in fibromuscular connective tissue - Open directly into urethra - mucosal glands - Tubolalveolar glands are found more peripheral in two zones 1. Inner = submucosal glands 2. Outer zone= main glands These are drained by excretory ducts opening on the two sides of the colliculus seminalis Glands produce glycoprotein, contain golgi apperatus -> pale staining Some glands have prostatic concretions in the lumen - Color depends on age and calcification Prostate has a connective tissue capsule with vessels, nerves and some occasional ganglion cells Stroma of prostate - Fibromuscular ct -> smooth muscle and fibers |
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Prostate - He 1. Prostatic utricle - Depression/fold on the posterior wall of the urethra - Remnant of the distal end of the Mullerian duct, which gives the fornices of the vagina - Lie between the ejaculatory ducts 2. Ejaculatory ducts - Star-shaped ducts - Pseudostratifed columnar epithelium |
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Seminal vesicle - He Seminal vesicle is a long coiled tube that appears in multiple cross-sections due to it shape. Epithelium is simple columnar - Some regions have pseudostratified - Lower and higher columnar - Secretory epithelium - No striated border Mucosa is very folded, with deep crypts without obvious connections with the surface Lamina propria - Contains elastic fibers and some smooth muscle cells Tunica muscularis - Inner circular and outer longitudinal layer - Not well defined Function - Produce ejaculatory fluid -> 60% - Fructose, amino acids, vitamin C, prostaglandins Contraction of the smooth muscle coat of the seminal vesicles during ejaculation causes the secretion into ejaculatory ducts and help flush the sperm out of the urethra |
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Seminal vesicle - He Epithelium changes, but is columnar Mucosa is very folded, giving deep crypts with no obvious connection to the surface |
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Penis glans - HE This slide is cut at the glans of penis Penis has two major components The corpus spongiosum will have abundant of elastic fibers, while in the corpus cavernous they are scarce. Outer wall of corpus cavernous is dense collagenous tissue - tunica albuginea. it's important that the spongy body remains it's elasticity during erection, to prevent compressing the urethra which runs inside the spongy body Corpus spongiosum - Bulbus penis - Corpus - Glands Corpus cavernousum - Crus penis - Corpus penis 1. Prepuce - foreskin Covered on it´s external and internal surface with stratified squamous keratinizing epithelium 2. Gap Between the prepuce and the surface of glans - Gap is not yet perfect in a baby penis - The gap is formed by the absorption of the middle cells by an inward proliferating epithelial lamina - A imperfect absorption of these cells cause a normal malformation, with cellular adhesion -> causing the prepuce cannot be withdrawn 3. Glans Formed by the ladle shaped corpus spongiosum, into which the tips of the cavernous bodies will protrude into - Depending on the level of the cut, the cavernous bodies may also be included in this slide as two patches surrounded by spongy bodies Skin of glands is pigmented, without hairfollicles, but may contain modified sebaceous glands 4. Urethra Will pierce the corpus spongiosum - Last portion of the urethra, distal to the navicular fossa - Lined by stratified squamous non-keratinizing epithelium - Separated by fibromuscular connective tissue 5. Frenulum Corpus spongiosum is fixed to the prepuce |
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Penis glans- He 1. Urethra 2. Glans 3. Glans and prepuce is not separated 4. prepuce |
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Penis - corpus spongiosum - He 1. Urethra 18-22cm - Intramural part: transitional epithelium - Prostatic urethra: transitional epithelium until collicus seminalis - Membranous utrethra: Stratified columnar - Spongy urethra: Stratified columnar, but stratified squamous non-keratininzg distal to the navicular fossa 2. Glands of littre - Mucous glands of Littre surrounds the urethra - Branched tubular glands - Open via paraurethral ducts - Endoepithelial glands in the epithelial of urethra 3. Cavernae - lined by endothelium and trabeculae with smooth msucles and connective tissue. - Trabeculae bulges into lumen when empty -> Ebner´s cushion - Cavernae are filled with blood during ejaculation 4. Corpus cavernosum 5. Connective tissue septum During erection 1. Icnreased arterial input - Size of lumen of helicane artery and central cavernae increase due to relaxation of muscles in trabecular 2. Decreased venous output -Compression of the peripheral cavernae veins - Pressed up along the tunica albuginea |
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Penis- corpus spongiosum - He Shows the cavernae lined with endothelium and the ebner´s cushions when empty |
