Enterochromaffin cell
Enterochromaffin (EC) cells, or "Kulchitsky cells", are a type of enteroendocrine and neuroendocrine cell occurring in the epithelia lining the lumen of the digestive tract and the respiratory tract that release serotonin.
Distribution
In the human gastrointestinal (GI) tract, the EC cells are distributed widely in the epithelium of the stomach,small bowel and colon.
Function
They use the rate-limiting enzyme tryptophan hydroxylase-1 (TPH-1) to synthesize serotonin and contain about 90% of the body's stores of serotonin (5-HT).
In the gastrointestinal tract, 5-HT is important in response to chemical, mechanical or pathological 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). Ondansetron is an antagonist of the 5-HT3 receptor and is an effective anti-emetic.
Origin
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.
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