Gastrin Inhibitory Peptide (GIP)
- Gastrin Inhibitory Peptide (GIP) is a peptide hormone that is synthesized by GI mucosal cells in the duodenum and jejunum of the small intestine and modulates post-prandial insulin release.
- Most types of nutrients (carbohydrates, proteins, and fats) directly act on GIP-secreting cells to induce secretion of GIP.
- The most important function of GIP is to directly induce secretion of insulin by beta cells of the endocrine pancreas. This may be why oral consumption of glucose causes more insulin release than an IV glucose load. Although GIP derives its namesake its capacity to inhibit release of gastrin and thus prevent excess stomach acid secretion, this functionality appears to be less important.