Enterochromaffin-like cell

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Enterochromaffin-like cell
Control-of-stomach-acid-sec.png
Control of stomach acid secretions. (ECL-cell at top center.)
Details
Location Gastric mucosa
Identifiers
Latin endocrinocytus ECL
MeSH D019861
TH H3.04.02.0.00030
Anatomical terms of microanatomy

Enterochromaffin-like cells or ECL cells are a type of neuroendocrine cell found in the gastric glands of the gastric mucosa beneath the epithelium, in particular in the vicinity of parietal cells, that aid in the production of gastric acid via the release of histamine. They are also considered a type of enteroendocrine cell. [1]

Contents

Function

Histamine Histamine.svg
Histamine

ECL cells synthesize and secrete histamine. These cells are stimulated by the hormones gastrin (not depicted in the adjacent diagram) and pituitary adenylyl cyclase-activating peptide. G cells are stimulated by vagal stimulation through the neurotransmitter gastrin-releasing peptide; this causes the G cells to secrete gastrin, which in turn stimulates ECL cells to release histamine. Note that this circuit is not activated by acetylcholine (ACh), which is of particular importance because the administration of atropine will not block the vagal stimulation of the G cells, as ACh is not the neurotransmitter for these cells.

However, ECL cells are activated directly by ACh on M1 receptors from direct vagal innervation leading to histamine release. This pathway will be inhibited by atropine. [2]

Gastrin is transferred from a specific type of G cell in the gastric epithelium to the ECL cells by blood. Histamine and gastrin act synergistically as the most important stimulators of hydrochloric acid secretion from parietal cells and stimulators of secretion of pepsinogen from chief cells. The most important inhibitor of the ECL cell is somatostatin from oxyntic D cells.

Enterochromaffin-like cells also produce pancreastatin and probably other peptide hormones and growth factors.

Clinical significance

A prolonged stimulation of these cells causes their hyperplasia. This is especially important in gastrinoma (the tumors in which there is an excessive secretion of gastrin), as this is one of the factors contributing to Zollinger–Ellison's syndrome. It was once believed that tumors of ECL origin form after a prolonged inhibition of gastric acid secretion, however there is no data to support this conclusion and proton pump inhibitors are not thought to contribute to gastric cancer. [3]

History

The name is derived from their location in the enteric system and their chromaffin-like staining pattern in histologic sections, which is characterized by silver staining.

See also

Related Research Articles

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Gastrointestinal physiology is the branch of human physiology that addresses the physical function of the gastrointestinal (GI) tract. The function of the GI tract is to process ingested food by mechanical and chemical means, extract nutrients and excrete waste products. The GI tract is composed of the alimentary canal, that runs from the mouth to the anus, as well as the associated glands, chemicals, hormones, and enzymes that assist in digestion. The major processes that occur in the GI tract are: motility, secretion, regulation, digestion and circulation. The proper function and coordination of these processes are vital for maintaining good health by providing for the effective digestion and uptake of nutrients.

The nervous system, and endocrine system collaborate in the digestive system to control gastric secretions, and motility associated with the movement of food throughout the gastrointestinal tract, including peristalsis, and segmentation contractions.

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References

  1. Enterochromaffin-like+Cells at the U.S. National Library of Medicine Medical Subject Headings (MeSH)
  2. Tobin G, Giglio D, Lundgren O (2009). "Muscarinic receptor subtypes in the alimentary tract" (PDF). Journal of Physiology and Pharmacology. 60 (1): 3–21. PMID   19439804.
  3. Thomson, Alan BR; Sauve, Michel D; Kassam, Narmin; Kamitakahara, Holly (21 May 2010). "Safety of the long-term use of proton pump inhibitors". World Journal of Gastroenterology. 16 (19): 2323–2330. doi: 10.3748/wjg.v16.i19.2323 . ISSN   1007-9327. PMC   2874135 . PMID   20480516.