GASTROENTEROPANCREATIC EFFECTS OF XENIN IN THE DOG

Xenin is a 25 amino acid peptide detected in the gastric mucosa of var ious mammals. It has since been found in low concentrations in other t issues. Xenin plasma concentrations increase after meals. The present study reports some gastroenteropancreatic effects of this peptide in t he dog. Intravenous infusion of 64 pmol/kg min synthetic xenin signifi cantly inhibited pentagastrin-stimulated gastric acid secretion and st imulated exocrine pancreatic secretion of volume and protein. Further, intravenous infusion of xenin in a dose of 1.0 pmol/kg min stimulated jejunal motility in the anaesthetized dog. An intravenous infusion of 32 pmol/kg min xenin raised plasma concentrations of pancreatic polyp eptide, vasoactive intestinal polypeptide, insulin and glucagon. The p resent experiments therefore indicate manifold bioactive properties of intravenously infused xenin in the dog, with jejunal motility the mos t sensitive target. Conclusions as to the physiological role of xenin cannot be drawn from the present experiments. The release of other hor monal peptides indicates a complex action of xenin. (C) Munksgaard 199 7.