Inhibition of Rat Gastric H+K+ATPaseIn Vivo. Relation to Reduction of Acid Secretion

The gastric acid secretion inhibitor, omeprazole, has been shown to inhibit the gastric H+K+ATPase isolated from hog stomach (1). The inhibitory action on the proton pump seems to be based on the fact that omeprazole, which is a weak base, accumulates in the acid compartments of the parietal cell. Here it is protonated and subsequently converted into an active form that exerts the inhibitory effect on the enzyme. In the present study, both the rate of gastric acid secretion and the activity of the H+K+ATPase isolated from the gastric corpus mucosa of rats during inhibition by omeprazole have been studied, in order to establish the relationship between gastric acid secretion and activity of the gastric H+K+ATPase.