Gastric secretion patterns
| Cell Type | Secretion |
|---|---|
| Goblet (mucus neck cell) | mucus |
| Chief cell | Pepsinogen |
| Parietal cell | Gastric acid (HCL) and intrinsic factor |
| G-cell | Gastrin |
| D-cell (see endocrine pancreas) | Somatostatin |
| Enterochromaffin-Like (ECL) cells (enteroendocrine cell) | Histamine |
hormone summary
| Secreted in | Stimulus | Inhibition | Actions | |
|---|---|---|---|---|
| Gastrin | G cells in antrum of the stomach | - Distension of stomach - Vagus nerves (mediated by GRP) - Luminal peptides/amino acids |
- Low antral pH - Somatostatin - Secretin - GIP (gastric inhibitory peptide) - Other hormones: VIP (vasoactive intestinal peptide), glucagon & calcitonin |
Increase HCL, pepsinogen and IF secretion, increases gastric motility, stimulates parietal cell maturation |
| Cholecystokinin (CCK) stops stomach from overloading duodenum |
I cells in upper small intestine | Fatty acids and certain amino acids (products of partially digested proteins and triglycerides) | Somatostatin | decreases gastric emptying, induces satiety Increases secretion of enzyme-rich fluid from pancreas, contraction of gallbladder and relaxation of sphincter of Oddi, trophic effect on pancreatic acinar cells |
| Secretin stops stomach from overloading duodenum |
S cells in upper small intestine | Acidic chyme in duodenum, fatty acids | Somatostatin | decreases gastric acid secretion, delay gastric emptying, stimulates the release of pepsinogen potentiates action of CCK Increases secretion of bicarbonate-rich fluid from pancreas and hepatic duct cells, trophic effect on pancreatic acinar cells, increases bile formation |
| VIP | Small intestine, pancreas | Neural | Stimulates secretion by pancreas and intestines, inhibits acid secretion | |
| Somatostatin | D cells in the pancreas & stomach | Fat, bile salts and glucose in the intestinal lumen | vagal stimulation | Decreases acid and pepsin secretion, decreases gastrin secretion, decreases pancreatic enzyme secretion, decreases insulin and glucagon secretion inhibits trophic effects of gastrin, stimulates gastric mucous production, inhibits CCK release & inhibits gastric emptying inhibits growth hormone |
| Histamine | ECL cells | Gastrin | stimulates gastric hydrochloric acid secretion |