Enteroendocrine System
Objective 10
18.10.1 Tabulate the hormones of the enteric nervous system: gastrin, cholecystokinin, secretin, glucose-dependent insulinotropic peptide, histamine, somatostatin, motilin.
18.10.2 For each hormone, describe the structure that produces the hormone, the target organ, and the action of the hormone.
| Summary of Enteroendocrine System | |||
|---|---|---|---|
| Hormone | Made By | Acts On | Action |
| Castrin | G cells of stomach | Stomach | Promote secretion of gastric juices |
| Cholecystokinin | Enteroendocrine cells of small intestine | Gallbladder
Pancreas Brain |
Ejection of bile; opening of sphincter of hepatopancreatic ampulla; more pancreatic juice; feel full |
| Secretin | Enteroendocrine cells (“S cells”) of duodenum | Pancreas | More bicarb in pancreatic juice |
| Glucose-dependent insulinotropic peptide (GIP) (Gastric Inhibitory Polypeptide) | Enteroendocrine cells (“K cells”) of duodenum & jejunum | Beta cells of pancreatic islets | Increase insulin secretion |
| Histamine | Mast cells of lamina propria | Parietal cells of the stomach | Increase acid secretion |
| Somatostatin | Hypothalamus | Many digestive organs | Decrease exocrine pancreas; decrease many hormone; slows gastric emptying |
| Motilin | Enteroendocrine cells (“M cells”) of duodenum & jejunum | Many digestive organs | Increase migrating myoelectric complexes, increase pepsin increase bowel motility |
A table summarizing the hormones of the enteroendocrine system is reproduced above. Most of these have been mentioned already, as part of earlier objectives. This table is mostly a review and synthesis of hormones we’ve already discussed.
For each row of the table, know the name of the hormone, where it is made, its target organ (“acts on” column), and its action.
