Histamine is secreted by:
- ECL cells lie in deep recesses of oxyntic glands & is associated with parietal cells of glands - Under influence of gastrin (secreted by G-cells), ECL cells release Histamine directly to deep oxyntic gland. Then histamine acts quickly to stimulate Hcl secretion Parietal cell / oxyntic cell: - Present in body of stomach & secrete Hcl & intrinsic factor (B12 vit absorption) - PH of this acid is about 0.8 (3 million times > PH of aerial blood) - Main driving force of Hcl secretion | Hydrogen-potassium pump (H+ - K+ adenosine triphosphatase ) - HCL secretion is under regulation of Endocrine = gastrin Neurocrine = Vagus (Ach) Paracrine = ECL (Histamine) - Chief / peptic cells Secrete large quantities of pepsinogen
Enterochromaffin cell
Parietal cell
Oxyntic cell
Chief cell
FMGE 2018