Gastric acid secretion, intraduodenal pH and gastroenteropancreatic hormone release to bombesin in antrocolic transposition dogs.

The effects of bombesin on gastric acid secretion from the Heidenhain pouch (HP), intraduodenal pH and gastroenteropancreatic (GEP) hormone levels were compared between 4 dogs with antrocolic transposition (ACT) and 4 non-ACT dogs. Bombesin, infused i.v. at a dose of 0.5 microgram/kg for one hr, produced a significant increase in gastric acid secretion from HP and a decrease in intraduodenal pH in both groups. However, these changes were more marked in ACT dogs. The intravenous infusion of bombesin also produced, in both groups, an increase in the plasma levels of gastrin, secretin, motilin, insulin, glucagon and pancreatic polypeptide (PP) with a different shape of curve for each hormone. Comparison between the two groups showed significantly greater plasma gastrin, secretin and insulin responses, and smaller plasma PP response in ACT dogs than in non-ACT dogs. These results demonstrate that the mechanism of GEP hormone release by bombesin may be complex and hormone responses to infusion of bombesin are influenced in a state of acid hypersecretion induced by ACT.