Enterochromaffin
Encyclopedia
Enterochromaffin cells (Kulchitsky cells) are a type of enteroendocrine
Enteroendocrine cells
Enteroendocrine cells are specialized endocrine cells of the gastrointestinal tract. They produce hormones such as serotonin, somatostatin, motilin, cholecystokinin, gastric inhibitory peptide, neurotensin, vasoactive intestinal peptide, and enteroglucagon....

 cell occurring in the epithelia lining the lumen
Lumen (anatomy)
A lumen in biology is the inside space of a tubular structure, such as an artery or intestine...

 of the digestive tract and the respiratory tract.

Function

They contain about 90% of the body's store of serotonin
Serotonin
Serotonin or 5-hydroxytryptamine is a monoamine neurotransmitter. Biochemically derived from tryptophan, serotonin is primarily found in the gastrointestinal tract, platelets, and in the central nervous system of animals including humans...

 (5-HT).

In the gastrointestinal tract, 5-HT is important in response to chemical, mechanical or pathological
Pathology
Pathology is the precise study and diagnosis of disease. The word pathology is from Ancient Greek , pathos, "feeling, suffering"; and , -logia, "the study of". Pathologization, to pathologize, refers to the process of defining a condition or behavior as pathological, e.g. pathological gambling....

 stimuli in the lumen. It activates both secretory and peristaltic reflexes, and activates vagal afferents (via 5-HT3 receptors) that signal to the brain (important in the generation of nausea
Nausea
Nausea , is a sensation of unease and discomfort in the upper stomach with an involuntary urge to vomit. It often, but not always, precedes vomiting...

). Ondansetron
Ondansetron
Ondansetron is a serotonin 5-HT3 receptor antagonist used mainly as an antiemetic , often following chemotherapy. Its effects are thought to be on both peripheral and central nerves...

 is an antagonist of the 5-HT3 receptor and is an effective anti-emetic.

They are stimulated by gastrin
Gastrin
In humans, gastrin is a peptide hormone that stimulates secretion of gastric acid by the parietal cells of the stomach and aids in gastric motility. It is released by G cells in the antrum of the stomach, duodenum, and the pancreas...

, a molecule that is produced at the antrum of the stomach by G cells.

Origin

They are derived from neural crest
Neural crest
Neural crest cells are a transient, multipotent, migratory cell population unique to vertebrates that gives rise to a diverse cell lineage including melanocytes, craniofacial cartilage and bone, smooth muscle, peripheral and enteric neurons and glia....

.

The enterochromaffin cells are derived from the same stem cells as the rest of the epithelium, and are not derived from the migratory neural crest source that provides the enteric nervous system
Enteric nervous system
The enteric nervous system is a subdivision of the autonomic nervous system that directly controls the gastrointestinal system in vertebrates.It is derived from neural crest.-Function:...

.

Etymology

They are called "entero"
meaning related to the gut and "chromaffin" because of a chromium
Chromium
Chromium is a chemical element which has the symbol Cr and atomic number 24. It is the first element in Group 6. It is a steely-gray, lustrous, hard metal that takes a high polish and has a high melting point. It is also odorless, tasteless, and malleable...

 salt reaction that they share with chromaffin cell
Chromaffin cell
Chromaffin cells are neuroendocrine cells found in the medulla of the adrenal gland and in other ganglia of the sympathetic nervous system. They are modified post-synaptic sympathetic neurons that receive sympathetic input...

s of the adrenal medulla
Adrenal medulla
The adrenal medulla is part of the adrenal gland. It is located at the center of the gland, being surrounded by the adrenal cortex. It is the innermost part of the adrenal gland, consisting of cells that secrete epinephrine , norepinephrine , and a small amount of dopamine in response to...

 (adrenal glands).

"Enterochromaffin-like cells"

Another population of chromaffin cells is found only in the stomach wall, called enterochromaffin-like cell
Enterochromaffin-like cell
Enterochromaffin-like cells or ECL cells are a type of neuroendocrine cells found in the gastric glands of the gastric mucosa beneath the epithelium, in particular in the vicinity of parietal cells. They are also considered a type of enteroendocrine cell....

s (ECL). They look like EC cells but do not contain 5-HT.

ECL cells respond to gastrin released by G-cells and they release histamine
Histamine
Histamine is an organic nitrogen compound involved in local immune responses as well as regulating physiological function in the gut and acting as a neurotransmitter. Histamine triggers the inflammatory response. As part of an immune response to foreign pathogens, histamine is produced by...

, which will stimulate the parietal cells to produce gastric acid
Gastric acid
Gastric acid is a digestive fluid, formed in the stomach. It has a pH of 1 to 2 and is composed of hydrochloric acid , and large quantities of potassium chloride and sodium chloride...

.

Pathophysiology

Neuroendocrine progenitor cells in the bronchial epithelium, the progenitors to Kulchitsky cells, have been implicated in the origin of small cell lung cancer.
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