Gastric H+/K+-ATPase
The gastric H+/K+-ATPase is an enzyme located in the tubu-lovesicular system and the apical membrane of the parietal cell and plays a crucial role in the process of gastric acid secretion. The enzyme catalyses an electroneutral exchange of H+ versus K+. It consists of a catalytic α-subunit and a heavily glycosylated β-subunit, both of which are rather homologous to their counterparts in Na+/K+-ATPase. In this review, molecular and genetic aspects of this enzyme are reviewed with reference to similar enzymes in other tissues.