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Control of Feeding - Anatomy & Physiology (view source)
Revision as of 10:11, 23 July 2008
, 10:11, 23 July 2008→Phases of Gastric Secretion
*Sight, smell, taste of food
*Sight, smell, taste of food
*Vagus nerve (CN X)
*Vagus nerve ([[Nervous System - CNS - Anatomy & Physiology#Innervation - Cranial Nerves|CN X]])
**Parasympathetic fibres
**Parasympathetic fibres
**Synapse in submucosal plexus
**Synapse in submucosal plexus
===Gastric===
===Gastric===
*Chemical and mechanical receptors in stomach respond to stretch and chemical stimulation
*Chemical and mechanical receptors in [[Forestomach - Anatomy & Physiology|stomach]] respond to stretch and chemical stimulation
*Increase in pH of gastric contents
*Increase in pH of gastric contents
*Response to undigested materials, especially proteins
*Response to undigested materials, especially proteins
*Histamine and gastrin released
*Histamine and [[Endocrine System - Gut - Anatomy & Physiology|gastrin]] released
*Negative feedback loop by sympathomimetic somatostatin released by paracrine method to inhibit gastrin secretion (when pH falls below 3)
*Negative feedback loop by sympathomimetic somatostatin released by paracrine method to inhibit [[Endocrine System - Gut - Anatomy & Physiology|gastrin]] secretion (when pH falls below 3)
*Submucosal and myenteric plexuses activated in vagus reflex arcs
*Submucosal and myenteric plexuses activated in vagus reflex arcs
===Intestinal===
===Intestinal===
*Chyme in the [[Duodenum - Anatomy & Physiology|duodenum]] inhibits acid secretion and motility by decreasing the stomach distension and increasing the stretch of the [[Duodenum - Anatomy & Physiology|duodenum]] leading to the enterogastric reflex
*Chyme in the [[Duodenum - Anatomy & Physiology|duodenum]] inhibits acid secretion and motility by decreasing the [[Forestomach - Anatomy & Physiology|stomach]] distension and increasing the stretch of the [[Duodenum - Anatomy & Physiology|duodenum]] leading to the enterogastric reflex
*A drop in pH below 4.5 causes release of secretin which inhibits parietal and chief cells and stimulate buffer release from the [[Pancreas - Anatomy & Physiology|pancreas]]
*A drop in pH below 4.5 causes release of secretin which inhibits parietal and chief cells and stimulate buffer release from the [[Pancreas - Anatomy & Physiology|pancreas]]