Parietal cells make acid and intrinsic factor, chief cells make pepsinogen, G cells make gastrin
Mnemonic
Five cell types, each with one product:
- Parietal (oxyntic) cells - hydrochloric acid and intrinsic factor. In the body and fundus
- Chief (peptic) cells - pepsinogen and gastric lipase
- Mucous neck cells - mucus and bicarbonate
- G cells - gastrin. In the antrum
- D cells - somatostatin, which inhibits everything
- Enterochromaffin-like cells - histamine, driving parietal cells through H2 receptors
“Parietal makes the acid and the intrinsic factor; chief makes the enzyme; G makes the gastrin.”
The intrinsic factor point is the clinically important one: autoimmune destruction of parietal cells causes both achlorhydria and pernicious anaemia, and it is also why gastrectomy and long term proton pump inhibitors risk B12 deficiency.
Expansion
| Cell | Secretion | Location |
|---|---|---|
| Parietal (oxyntic) | Hydrochloric acid, intrinsic factor | Body and fundus |
| Chief (peptic) | Pepsinogen, gastric lipase | Body and fundus |
| G cell | Gastrin | Antrum |
| Mucous neck | Mucus, bicarbonate | Throughout |
| Enterochromaffin-like | Histamine | Body and fundus |
| D cell | Somatostatin | Antrum and body |
The regional split is the key: acid comes from the body, the hormone that drives it comes from the antrum.
Autoimmune destruction of parietal cells causes both achlorhydria and B12 deficiency through loss of intrinsic factor. A gastrin-secreting tumour causes Zollinger-Ellison syndrome, with multiple refractory ulcers. And because gastrin release is inhibited by acid, antrectomy or acid suppression alters the feedback loop in predictable ways.