Regarding cholecystokinin-pancreozymin (CCK-PZ), all are true except (Repeat 2007 Q 42)
High-Yield Explanation
Ans: a (Pepsinogen secretion is increased by gastrin and not by CCK-PZ)Pepsinogen secretion is increased by gastrin and not by CCK-PZ.Important points on GI hormones: CCK-PZSecretionGastrinFromJejunum (I cells)Uppersmall intestine (S cells)Antral portion of stomach (G cells)Stimulus- Protein digestion products- Protein digestion productsLuminal- protein products, distention- Fatty acids- Acids bathing mucosaNeural- vagal discharge (GRP)Blood- calcitonin, epinephrineAction1) Delays gastic emptying (Pyloric sphincter contra.)1) | HCO3- rich pancreatic juice1) Stimulate gastric acid & pepsin2) | duodenal emptying2) Augments action of CCK2) Trophic to stomach mucosa3) | motility of intestine & colon3) | gastric acid secretion3) Gastric motility4) | pancreatic secretion (enzyme rich)4) Pyloric sphincter contr.4) Stimulate insulin secretion5) Stimulate secretion6) GB contraction7) | glucagon secretion8) Trophic to pancreas