Function of K+-Cl- cotransporters in the acid secretory mechanism of gastric parietal cells

Abstract

Gastric proton pump (H+,K+-ATPase) secretes H + of acid (HCl) via the luminal membrane of parietal cells. For the HCl secretion, Cl-- and K+-transporting proteins are required. Recent our studies have demonstrated that K+-Cl- cotransporters (KCC3a and KCC4) are expressed in gastric parietal cells. KCC3a is associated with Na+,K+-ATPase in the basolateral membrane, and KCC4 is associated with H+,K+-ATPase in the apical canalicular membrane. This paper summarizes the functional association between KCCs and P-type ATPases and the contribution of these complexes to acid secretion in gastric parietal cells. © 2011 Pharmaceutical Society of Japan.