GENERAL HISTOLOGY

Detailed explanation-1: -Final answer: HCl Is secreted by Parietal Cell of the stomach.

Detailed explanation-2: -Parietal cells within the stomach lining secrete hydrochloric acid that lowers the pH of the stomach. A low pH (1.5 to 2) activates pepsin. Acetylcholine, gastrin, and histamine stimulate the proton pump in parietal cells to release hydrogen ions and decrease pH.

Detailed explanation-3: -Hydrochloric acid secreted from gastric parietal cells generates the strongly acidic environment of the gastric lumen (pH <2) (305), which kills food-derived bacteria, facilitates food digestion, and promotes absorption of minerals including phosphate, calcium, and iron.

Detailed explanation-4: -Parietal cells are also referred to as oxyntic cells, based on the Greek word oxyntos (to generate an acidic substance). The “typical” parietal cell is usually depicted in a triangular shape with the apical region of the cell forming the apex of the triangle, which borders the lumen of the gastric gland.

Detailed explanation-5: -Parietal cells express histamine H2-type receptors, muscarinic M3 receptors, and gastrin/CCK-2 or B-type receptors. Although gastrin plays a central role in the stimulation of gastric acid secretion, this hormone has minimal effects on the acid secretory response when administered to parietal cells in isolation.