ATP4A(redirected from gastric hydrogen-potassium ATPase)
ATP4AA gene on chromosome 19q13.1 that belongs to a family of P-type cation-transporting ATPases; it is composed of heterodimers consisting of a high molecular weight catalytic alpha subunit and a smaller, heavily glycosylated beta subunit, which catalyse the hydrolysis of ATP coupled with the exchange of H+ and K+ ions across the plasma membrane and are responsible for gastric acid secretion. Overactivity of H+, K+-ATPases causes gastric inflammation; these transporters are the pharmacologic target in the treatment of peptic ulcer disease, dyspepsia and gastro-oesophageal reflux disease (GERD/GORD).
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