Gastrin derivatives investigated for secretory potency and for changes in gastric mucosal histamine formation

1. Acid secretion and rate of histamine formation in the gastric mucosa were determined in rats after injection of hog gastrin II, gastrin pentapeptide and some substituted analogues of the C-terminal tetrapeptide of gastrin.2. Accelerated mucosal histamine formation was induced by hog gastrin II, gastrin pentapeptide and those analogues which elicited acid secretion, whereas secretorily inactive derivatives did not alter histamine formation.