- Which type of cells located in gastric glands is responsible for the release of histamine?
(1) Mucus neck cells (2) Enterochromaffin like cells
(3) Cheif cells (4) Parietal cellsHistamine, a vital bioactive amine, plays an essential role in the regulation of gastric acid secretion. Within the gastric glands of the stomach, certain specialized cells produce and release histamine, which acts as a potent stimulator of acid secretion by parietal cells. Understanding which cells are responsible for histamine secretion is crucial to grasp the intricate control of digestive processes.
Cells in the Gastric Glands and Their Functions
The gastric glands consist of various cell types, each with specific roles:
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Parietal cells: Secrete hydrochloric acid (HCl) and intrinsic factor necessary for vitamin B12 absorption.
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Chief cells: Produce pepsinogen, the inactive precursor of pepsin, which digests proteins.
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Mucus neck cells: Secrete mucus to protect the stomach lining.
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Enterochromaffin-like (ECL) cells: Specialized neuroendocrine cells responsible for releasing histamine.
Enterochromaffin-Like Cells and Histamine Release
Enterochromaffin-like (ECL) cells are located primarily in the corpus (body) region of the stomach within the gastric glands. These cells synthesize and store histamine, releasing it in response to stimuli such as the hormone gastrin and neuronal inputs.
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Histamine Function:
Histamine released by ECL cells binds to H2 receptors on adjacent parietal cells. This binding activates intracellular signaling pathways that stimulate the parietal cells to secrete hydrochloric acid. -
Regulation:
The release of histamine by ECL cells is tightly controlled by gastrin, acetylcholine, and somatostatin, ensuring appropriate acid secretion levels.
Why Other Cells Are Not Responsible
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Mucus neck cells: Primarily secrete protective mucus, not histamine.
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Chief cells: Focus on secreting pepsinogen, unrelated to histamine production.
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Parietal cells: Although they respond to histamine, they do not produce it.
Summary Table: Gastric Cells and Their Secretions
Cell Type Secretions Role Enterochromaffin-like cells (ECL) Histamine Stimulate acid secretion via parietal cells Parietal cells Hydrochloric acid, intrinsic factor Acid secretion and vitamin B12 absorption Chief cells Pepsinogen Protein digestion Mucus neck cells Mucus Protect gastric mucosa Conclusion
The cells located in the gastric glands responsible for the release of histamine are the enterochromaffin-like (ECL) cells. Their histamine secretion plays a pivotal role in activating parietal cells to produce gastric acid, essential for digestion.
Therefore, the correct answer is:
(2) Enterochromaffin-like cells -
