The interaction of K+ with gastric parietal cells and gastric ATPase

Abstract

The gastric H+ secretion in isolated cell requires K+ and is ATP dependent. There is also evidence in the cell system for Na+ inhibition of H+ secretion. The isolated gastric ATPase also shows K+ activation and inhibition by K+ or Na+ located on the ATP binding side of the enzyme, which corresponds to the cytoplasmic face of the enzyme. Gastric vesicles are activated in terms of transport activity by internal K+, and this site, inhibited by reagents that modify carboxyl groups, is required for enzyme turnover and transport.