Function of secretin is?

Ans. D Bicarbonate secretion from pancreasRef: Quantitative Human Physiology; An Introduction, pg. 711-712Important differences between GIT hormones (Gastrin, CCK, Secretin, GIP) GastrinCCKSecretinGIPSiteMain site: G cells (antrum)I-cells of the proximal two- thirds of small intestineS-cells: Upper small intestineK-cells: Proximal intestinal cryptsActionsMajor:* Stimulate acid and pepsin secretion* Stimulate gastric motility* Act as growth factor to stimulate mucosal proliferationMajor:* Stimulate pancreatic acinar cell enzyme secretion* Stimulate GB contraction* Relaxes sphincter of oddi* Inhibits gastric acid secretion and gastric emptying* Pyloric sphincter contraction* Major: Secretion of HCO3 from biliary and pancreatic ductular cell and Brunner gland.* Inhibit gastric acid secretion* Stimulate pyloric sphincter* Increases bile flow* Augments the action of CCKMajor: Stimulate insulin release from pancreasMajor stimulusPeptides (most potent)Distension of stomach CalciumGRP (gastrin releasing peptides)Peptides (most potent)Fatty acid (BUT NOT TG)Acid (most potent)Digestive proteinGlucose, fat and amino acid