D: Inhibit the H+/K+ ATPase enzyme in parietal cells

Sat, 18 Apr 2026 09:33:52 +0000

# Understanding the Inhibition of H+/K+ ATPase in Parietal Cells: A Key in Gastric Physiology and Therapeutics The stomach is a dynamic organ central to digestion, and one of its most important cells—the parietal cell—plays a critical role in acid secretion. Located in the gastric glands of the stomach lining, parietal cells are responsible for producing hydrochloric acid (HCl) by regulating the H+/K+ ATPase enzyme, also known as the proton pump. This enzyme actively transports hydrogen ions (H+) into the gastric lumen in exchange for potassium ions (K+), creating the highly acidic environment essential for protein digestion, pathogen defense, and activating digestive enzymes. ### What is the H+/K+ ATPase Enzyme? The H+/K+ ATPase is a specialized proton pump embedded in the cortical membrane of parietal cells. Unlike typical ion transporters, it effectively exchanges one H+ for one K+, effectively secreting hydrogen ions into the stomach lumen while bringing potassium back into the cell. This process generates gastric acid, maintaining a pH between 1 and 3 in the stomach—a crucial factor for normal digestive function.