Parietal Cells (Stomach)

Parietal Cells are specialized cells that line the walls of the stomach. They play a key role in the production of hydrochloric acid and Castle factor, necessary for the digestion of food.

Parietal cells contain a large number of mitochondria, which provide energy for the secretion of hydrochloric acid. In addition, these cells have an extensive system of tubules and vesicles through which hydrochloric acid enters. When stimulated, parietal cells actively release HCl into the gastric lumen, sharply lowering the pH level.

Thus, parietal cells play a critical role in maintaining the acidity of gastric juice, necessary for normal digestion. Violation of their function leads to the development of gastritis and peptic ulcers.

Gastric parietal cells: functional significance and evolutionary dynamics

Parietal cells (Parietal cells) are secretory cells of the glandular epithelium of the gastric glands (or M-cells), located in the area of ​​the body and fundus of the stomach in the fundus projection (DPC). The function of parietal cells is reduced to the formation and release of hydrochloric acid (HCl) into the lumen of the stomach from the lumen of the duct merging with the fundus of the gastric gland. For the first time, by the way, gastric physiology in Russia was developed by employee I.P. Pavlova - Professor V.M. Bekhterev. At an international conference in 1937, V.F. Alenikov put forward hydrochloric acid as one of the main stimuli for the formation of hydrochloric acid in the stomach. There are suggestions that parietal and chief cells are regulated by the same humoral components or may be under the same regulatory humoral influence. Indeed, RNA-protein complexes have recently been identified that respond to both the histamine H2 receptor and the gastrinparietal chain; previously unknown receptors responsible for the excitation of chief cells were discovered. There is a hypothesis that a similar effect of hypochlorous acid in the “inner layer” of gastric contents, which affects the basic mechanism of secretion of pH units of the main and parietal gastric cells, can, under certain conditions, increase the level of histamine H2 in the “inner layer”, which stimulates the formation of hydrochloric acid and an increase in parietal cells in the body. The density of the parietal glandular cells decreases from the pyloric part of the stomach towards the cardiac part of the stomach. This corresponds to a decrease in the pH value contained in the lumen of the stomach, with an increase in the level of amioacylcarboxylic acid (AA) and an increase in pepsin in the lumen of the body of the stomach during the transition from the cardiac to the pyloric region. The density of cell distribution is also characterized by a different ratio of parietal-chief cells in the body and pylorus: the body of the stomach contains more parietal (insulinate and gliadein) cells, while there are fewer of them in the pyloric stomach.