Effect of intestinal hormones and peptides on intragastric pressure in dogs.

Intragastric pressure was measured in dogs with gastric fistulas by using a flaccid balloon containing 500 ml of water. Intravenous infusion of cholecystokinin (20% pure), the carboxyl-terminal octapeptide of cholecystokinin, secretin, and vasoactive intestinal peptide produced dose-related decreases in intragastric pressure with maximal decreases of 40% or more. Glucagon and gastric inhibitory peptide produced smaller decreases in intragastric pressure. Motilin caused a dose-related increase in intragastric pressure that lasted only about 7 min despite continuing infusion of the peptide. The half-dose of cholecystokinin or of octapeptide of cholecystokinin for pancreatic protein secretion and the half-dose of secretin for pancreatic bicarbonate secretion each produced significant inhibition of intragastric pressure, suggesting that these hormones play a physiological reole in regulating gastric pressure.