[Secretion of pancreatic polypeptide in cats in response to different stimuli; correlation with gastric acid...

The pancreatic polypeptide response to a meal depends on various mechanisms, which are only partly understood. The aim of this study was to define whether humoral factors and nutrients which modulate postprandial gastric acid secretion play a role in the regulation of pancreatic polypeptide secretion. Our study was performed in the cat, a species in which pancreatic polypeptide release has never been explored. The animals were provided with a gastric fistula and a Heidenhain pouch and received, in a random order, mixed liver (50 g) per os or different nutriments which were introduced directly into the gastric fistula in identical final volumes: 50 g mixed liver; 1.5 to 12 g oligopeptides; or 2 g of triglycerides or glycogen. Acid output and pancreatic polypeptide secretion were measured over 150 min. In the cat as in dog and man, a mixed meal induced a five to ten-fold increase of plasma pancreatic polypeptide. The protein fraction of the meal was the most potent stimulus for release of this peptide and the pancreatic polypeptide response to protein seemed to be dose-related. The lipid and carbohydrate components of the meal were only weak stimulants. In the cat, a central vagal stimulation is effective on pancreatic polypeptide release, as on gastric acid secretion, since 2-deoxyglucose stimulated both secretions (about 15 p. 100 of maximal response to a meal). The integrated pancreatic polypeptide release and the Heidenhain pouch acid secretion in response to nutriments were correlated during the 30-120 min period.(ABSTRACT TRUNCATED AT 250 WORDS)