[Role of antral histamine and gastrin in gastric acid secretion: experimental facts and hypotheses].

Histamine isolated from the gastric antral mucosa probably potentiates the secretory activity of gastrin by suppression of the inhibitory effect of somatostatin on gastrin. In dogs with gastric fistula and Heindenhain pouch, acid secretion was obtained in response to exogenous gastrin, antral histamine or various combinations of both stimulants. Acid output was expressed by graphic representation: the administered doses of gastrin and antral histamine were reported respectively, on the X and Y axis, the acid output values were plotted on the intersection of the stimulant dosages used, and curves of equal acid outputs were drawn. This representation was used to approach the physiological and physiopathological mechanisms of gastric secretion, considering that gastrin and antral histamine could be the main parameters. It also seems possible that an histaminic factor could be involved in secretion processes. Excess or lack of one of the other stimulants could be responsible for an increased or a decreased secretory response: these facts can be related to the curves of high acid output or low acid output observed in the animal. Thus, histamine, especially of antral origin, might be an important component of the secretion mechanism, by modulation of gastrin activity; both substances could be the main mediators of somatostatin-induced inhibition.