IMPLICATION OF GASTRIC MUCOSAL HISTAMINE IN INHIBITION BY ISOPRENALINE OF PENTAGASTRIN‐INDUCED GASTRIC SECRETION

Abstract

1 The effect of isoprenaline on pentagastrin-induced gastric secretion was studied in conscious rats with Heidenhain pouches. The influence of isoprenaline on pentagastrin-induced release and formation of gastric mucosal histamine was also examined. 2 Isoprenaline strongly inhibited pentagastrin-induced acid secretion, an inhibition which could not be overcome by increasing the dose of pentagastrin. 3 Propranolol blocked the inhibitory effect of isoprenaline on pentagastrin-induced acid secretion. 4 Isoprenaline enhanced pepsin secretion induced by pentagastrin, an effect which was blocked by propranolol. 5 Isoprenaline reduced the increase in formation and release of gastric mucosal histamine following pentagastrin infusion, an inhibitory influence which was almost completely blocked by propranolol. 6 The inhibition by isoprenaline of pentagastrin-induced acid secretion is tentatively related to alterations in gastric mucosal histamine occurring simultaneously.