11:067:450 Lecture Notes - Lecture 15: Motilin, Incretin, Pancreatic Duct
4 Apr 2016
School
Department
Course
Professor
Document Summary
S cells produce secretin and secretin is necessary for the bicarbonate release from pancreatic duct cells and bile duct cells. Luminal secretin releasing factor activates the s cells to produce the secretin which activates not only the bicarbonate solution but also activates the chief cells and the d cells to produce somatostatin. Somatostatin is produced in the duodenum region and the pancreas as well. It can downregulate the activity of the s cells and the ecl cells (which produce histamines) and the parietal cells (which produce the acid) and g cells (which produce gastrin). All these gi hormones such as secretin, gastrin, somatostatin and pancreatic enzymes play a role in the initial digestion in the duodenum. There is much more absorption in the jejunum and ileum. The gip which is the glucose dependent insulinotropin enhances the amount of insulin produced. The cleavages in the propeptide that release the glucagon is very cell-type specific.
