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'''Sympathetic''' fibres run with the arteries. '''Parasympathetic''' fibres from the '''vagus''' nerve ([[Cranial Nerves - Anatomy & Physiology|CN X]]) are within the two vagal trunks. In the '''proximal''' region of the stomach, vagal stimulation '''suppresses''' muscular contraction (VIP); In the '''distal''' region, vagal stimulation '''increases''' muscular activity (ACh).
 
'''Sympathetic''' fibres run with the arteries. '''Parasympathetic''' fibres from the '''vagus''' nerve ([[Cranial Nerves - Anatomy & Physiology|CN X]]) are within the two vagal trunks. In the '''proximal''' region of the stomach, vagal stimulation '''suppresses''' muscular contraction (VIP); In the '''distal''' region, vagal stimulation '''increases''' muscular activity (ACh).
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==Histology==
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[[Image:Glandular Stomach Histology Dog.jpg|thumb|right|150px|Glandular Stomach Histology Dog- Copyright RVC 2008]]
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*Columnar epithelium
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*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:
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**Serosa/adventitia
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**Tunica muscularis
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**Submucosa
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**Mucosa
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*Chief (zygomatic) cells secreting pepsinogen
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**Secreted in response to vagus and gastrin
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**Basophilic
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**More abundant in base of glands
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**Pepsinogen unfolds and cleaves itself (autocatalyses) in response to hydrochloric acid
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**Only active in acidic envrionments
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[[Image:Fundic region of glandular stomach.jpg|thumb|right|150px|Fundic Region of Glandular Stomach (Parietal and Chief cells)- Copyright RVC 2008]]
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*Goblet cells secreting mucous
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**Protects against autodigestion
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*Parietal (oxyntic) cells secreting hydrochloric acid in gastric pits
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**Aids digestion
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**Activates gastric enzymes, e.g. pepsinogen to pepsin
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**Kills microorganisms and enzymes that enter with food
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**Secreted in response to vagus or pepsin 
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**Large, pyramid shaped
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**More abundant in upper region of glands
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*Gastrin from pyloric G cells
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*Somatostatin from pyloric D cells
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*Histamine from Enterochromaffin-like cells (ECL cells)
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[[Image:Lamina muscularis 3 regions.jpg|thumb|right|150px|Lamina Muscualris 3 Regions - Copyright RVC 2008]]
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*3 layers of lamina muscularis: the outer longitudinal, middle circular and inner oblique.
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*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.
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*Lymphatic vessels are present in the submucosa
    
==Digestive Enzymes==
 
==Digestive Enzymes==
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Click here for [[Control of Feeding - Anatomy & Physiology|Control of Feeding]].
 
Click here for [[Control of Feeding - Anatomy & Physiology|Control of Feeding]].
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Click here for [[Stomach - Histology|stomach histology]].
      
'''Video links:'''
 
'''Video links:'''
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