noun, plural: parietal cells
Any of the epithelial cells in the gastric gland responsible for the secretion of hydrochloric acid, intrinsic factor, and bicarbonates
The gastric glands are the glands located in the stomach lining and are responsible for the secretion of the major components of the gastric juice. There are different cell types that make up the gastric glands. The different cell types are: (1) parietal cells, (2) gastric chief cells, (3) foveolar cells, particularly the mucous neck cells, (4) G cells, and (5) enterochromaffin-like cells.
The parietal cells are responsible for the secretion of hydrochloric acid (HCl), bicarbonates, and intrinsic factor (a glycoprotein that aids in vitamin B12 absorption). These cells are located mainly in the fundic and in the cardiac regions of the stomach.
The parietal cell forms a canaliculus, i.e. a deep infolding resulting in the formation of little channel. The canaliculus increases the surface area for secretion. When the parietal cell is activated, it forms several canaliculi and release hydrochloric acid by active transport (via H–/K+ ATPases, enzymes unique to the parietal cells) into the lumen of the stomach. Gastric HCl helps in the promotion of protein denaturation during digestion. It also activates pepsinogen, which aids in the digestive process by breaking the peptide bonds that have become exposed from protein denaturation.
- oxyntic cell
- delomorphous cell