GIP is a forty-two amino-acid peptide that is produced by K cells in the upper small intestinal mucosa. It was originally thought to inhibit gastric secretions (gastric inhibitory peptide), but this proved to be a pharmacological action. At physiological doses, GIP is a component of the enteroinsular axis, stimulating prandial insulin release. Such insulin-releasing factors are known as ΓÇÿincretinsΓÇÖ. Thus, food ingestion, particularly of carbohydrate and long-chain fatty acids, is the stimulus for GIP secretion.
In common with other members of this family of peptides, it inhibits secretion of gastric acid and stimulates insulin release, although these effects occur only at pharmacological doses.
