This GIP fragment has potent insulinotropic activity in the isolated, perfused rat pancreas but greatly reduced somatostatinotropic activity in the isolated perfused rat stomach. The site responsible for insulinotropic activity apparently lies between residues 19 and 30 of GIP.
GIP (1-30) amide, porcine TFA is a high-affinity full agonist of the glucose-dependent insulinotropic polypeptide (GIP) receptor, having a similar potency as the native GIP(1-42) [1]. Furthermore, GIP (1-30) amide, porcine displays weak inhibitory effects on gastric acid secretion while exhibiting potent insulin-stimulating properties.