How secretion of gastric juice is controlled in stomach?
The production of gastric acid is regulated both by the autonomic nervous system and by several hormones. Also, the production is tightly regulated by positive regulators and negative feedback mechanisms. Four types of cells are involved in this process: parietal cells, G-cells, D-cells, and enterochromaffin-like cells. Nerve endings (vagus nerve) in the stomach secrete two stimulating neurotransmitters: acetylcholine and gastrin-releasing peptide. Their effect both directly on parietal cells, and is mediated by the secretion of gastrin from G cells and histamine from enterochromaffin-like cells. Gastrin acts on the parietal cells directly and indirectly, stimulating the release of histamine. The release of histamine is the most important mechanism for the positive regulation of gastric acid secretion in the stomach.