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Monogastric Stomach - Anatomy & Physiology (view source)
Revision as of 13:03, 6 September 2010
, 13:03, 6 September 2010no edit summary
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−*Columnar epithelium
−
−*Folded mucosa forming longitudinal rugae
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−*Invaginations called gastric pits which are continuous with gastric glands
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−*The 4 layers of the stomach wall are:
−**Serosa/adventitia
−**Tunica muscularis
−**Submucosa
−**Mucosa
−
−*Chief (zygomatic) cells secreting pepsinogen
−**Secreted in response to vagus and gastrin
−**Basophilic
−**More abundant in base of glands
−**Pepsinogen unfolds and cleaves itself (autocatalyses) in response to hydrochloric acid
−**Only active in acidic envrionments
−
−[[Image:Fundic region of glandular stomach.jpg|thumb|right|150px|Fundic Region of Glandular Stomach (Parietal and Chief cells)- Copyright RVC 2008]]
−*Goblet cells secreting mucous
−**Protects against autodigestion
−
−*Parietal (oxyntic) cells secreting hydrochloric acid in gastric pits
−**Aids digestion
−**Activates gastric enzymes, e.g. pepsinogen to pepsin
−**Kills microorganisms and enzymes that enter with food
−**Secreted in response to vagus or pepsin
−**Large, pyramid shaped
−**More abundant in upper region of glands
−
−*Gastrin from pyloric G cells
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−*Somatostatin from pyloric D cells
−
−*Histamine from Enterochromaffin-like cells (ECL cells)
−
−[[Image:Lamina muscularis 3 regions.jpg|thumb|right|150px|Lamina Muscualris 3 Regions - Copyright RVC 2008]]
−*3 layers of lamina muscularis: the outer longitudinal, middle circular and inner oblique.
−
−*Glands are short, coiled, branched tubular. Need to be replaced due to wear and tear. Only in mucosal layer.
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−*Cardia is a narrow muscle strip
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−*Pyloric sphincter is thickened tunica muscularis from the middle circular smooth muscle layer
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−*In fundic region, tunica muscularis is thinner, glands are straight and gastric pits are shallow. Abundance of parietal and cheif cells in gland.
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−*In pyloric region, tunica muscularis is thicker, glands are coiled and gastric pits are deep.
−
−*Lymphatic vessels are present in the submucosa
**Greater omentum- connceting the greater curvature of the stomach to the [[Duodenum - Anatomy & Physiology|duodenum]] and dorsal body wall
**Greater omentum- connceting the greater curvature of the stomach to the [[Duodenum - Anatomy & Physiology|duodenum]] and dorsal body wall
−==Histology==
+==[[Stomach - Histology|Histology]]==
−[[Image:Glandular Stomach Histology Dog.jpg|thumb|right|150px|Glandular Stomach Histology Dog- Copyright RVC 2008]]
−==Vasculature==
==Vasculature==