A gastric parietal cell, also known as an oxyntic cell, is a specialized cell found in the lining of the stomach. It plays a crucial role in the production of hydrochloric acid (HCl), a vital component for the digestive system. Gastric parietal cells are primarily located in the gastric pits of the stomach's inner lining, known as the gastric mucosa.
The main function of gastric parietal cells is to secrete HCl in response to various stimuli. These cells contain microscopic structures called tubulovesicles, which store and release the acid. When stimulated, these tubulovesicles fuse with the cell membrane, releasing HCl into the stomach lumen. This acid aids in the breakdown of food and facilitates the activation of digestive enzymes.
Additionally, gastric parietal cells produce an intrinsic factor, a glycoprotein essential for vitamin B12 absorption in the small intestine. The intrinsic factor complexes with vitamin B12 and allows its absorption in the ileum.
Gastric parietal cells are regulated by various factors, including hormones such as gastrin, histamine, and acetylcholine. These hormones stimulate the activation and proliferation of parietal cells, ensuring the proper production of HCl.
Overall, gastric parietal cells are critical for the body's digestive processes. Their secretion of hydrochloric acid and intrinsic factor significantly contribute to the breakdown and absorption of nutrients, promoting overall digestive health.
