Intrinsic factor of castle is secreted by which of the following ceils in gastric glands –
**Core Concept**
Intrinsic factor is a glycoprotein produced by the stomach that plays a crucial role in vitamin B12 absorption. It binds to vitamin B12 in food and facilitates its absorption in the small intestine.
**Why the Correct Answer is Right**
Intrinsic factor is secreted by the parietal cells in the gastric glands of the stomach. These cells produce and secrete hydrochloric acid (HCl) and intrinsic factor into the gastric lumen. The intrinsic factor-vitamin B12 complex is then released into the duodenum, where it binds to specific receptors on the surface of enterocytes, enabling vitamin B12 absorption.
**Why Each Wrong Option is Incorrect**
**Option A:** Chief cells are responsible for secreting pepsinogen, the inactive precursor to pepsin, and are not involved in intrinsic factor production.
**Option B:** Mucous neck cells produce mucus that protects the gastric mucosa from acid and pepsin, but they do not secrete intrinsic factor.
**Option C:** Enterochromaffin-like (ECL) cells release histamine, which stimulates parietal cells to secrete HCl, but they do not produce intrinsic factor themselves.
**Clinical Pearl / High-Yield Fact**
The absence of intrinsic factor leads to pernicious anemia, a condition characterized by megaloblastic anemia due to vitamin B12 deficiency. This condition is often associated with autoimmune gastritis, where the immune system targets and destroys parietal cells responsible for intrinsic factor production.
**Correct Answer: C. Parietal cells.