Which cells in the stomach produce hydrochloric acid (HCl)?

The production of hydrochloric acid (HCl) in the stomach is primarily carried out by parietal cells. These cells are located in the gastric glands of the stomach lining. Parietal cells secrete HCl as well as intrinsic factor, which is essential for the absorption of vitamin B12 in the intestines.

HCl plays several crucial roles in digestion, including aiding the breakdown of food particles, activating digestive enzymes, and maintaining an acidic environment that helps kill harmful bacteria. The secretion of HCl is regulated by various factors, including the presence of food in the stomach and neural signals from the central nervous system.

In contrast, chief cells are responsible for producing pepsinogen, an inactive precursor of the enzyme pepsin, which becomes active in the acidic environment created by HCl. G cells produce gastrin, a hormone that stimulates parietal cells to release HCl. Mucous cells primarily secrete mucus, which protects the stomach lining from the corrosive effects of acid. Therefore, the parietal cells are uniquely tasked with the critical function of HCl production in the stomach.