MRCP UK EXAMINATIONS

Detailed explanation-1: -Gastrin is a peptide hormone primarily responsible for enhancing gastric mucosal growth, gastric motility, and secretion of hydrochloric acid (HCl) into the stomach. It is present in G cells of the gastric antrum and duodenum.

Detailed explanation-2: -Gastrin is a peptide hormone that stimulates secretion of gastric acid (HCl) by the parietal cells of the stomach and aids in gastric motility. It is released by G cells in the pyloric antrum of the stomach, duodenum, and the pancreas.

Detailed explanation-3: -Gastrin stimulates histamine synthesis and secretion in enterochromaffin-like cells via CCK2R; gastric acid secretion is subsequently induced via the histamine-2 receptor in parietal cells. In addition, gastrin elicits the release of gastric acid through CCK2R in parietal cells.

Detailed explanation-4: -Gastrin secreted from G cells binds directly on parietal cells or stimulates acid secretion mediated by histamine release from ECL cells.

Detailed explanation-5: -Gastrin is released from G cells located in the gastric antrum and stimulates enterochromaffin-like (ECL) cells to release histamine, which in turn directly activates acid secretion from the nearby parietal cell.