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Published on: September 23, 2015
5-HT (serotonin) physiology and related drugs
1Department of Anatomy and Cell Biology, Columbia University College of Physicians and Surgeons, New York, NY 10032, USA. mdg4@columbia.edu
Current Opinion in Gastroenterology
|October 7, 2006
Summary
The gut
Area of Science:
- Gastroenterology
- Neuroscience
- Cell Biology
Background:
- The gut possesses intrinsic neural reflexes independent of the central nervous system.
- Enterochromaffin (EC) cells secrete serotonin (5-hydroxytryptamine, 5-HT), mediating gut reflexes.
- Serotonin 5-HT signaling is crucial for gut function and neuronal development.
Purpose of the Study:
- To elucidate the role of serotonin (5-HT) in gut physiology and its implications in irritable bowel syndrome (IBS).
- To investigate the function of the serotonin reuptake transporter (SERT) in the gut.
- To explore the developmental role of 5-HT in enteric neurons.
Main Methods:
- Investigated serotonin secretion by EC cells and its action on intrinsic and extrinsic primary afferent neurons.
- Examined the role of serotonin reuptake transporter (SERT) in 5-HT inactivation.
- Reviewed evidence linking abnormal 5-HT signaling to IBS pathogenesis.
- Discussed the function of 5-HT in enteric neuron development via 5-HT(2B) receptors.
Main Results:
- Serotonin (5-HT) released by EC cells activates intrinsic neurons (via 5-HT1P/4 receptors) for peristalsis and extrinsic neurons (via 5-HT(3) receptors) signaling distress.
- Epithelial serotonin reuptake transporter (SERT) inactivates gut 5-HT.
- Abnormal 5-HT signaling is implicated in IBS, causing visceral hypersensitivity and motility issues.
- 5-HT acts as a growth factor for enteric neurons, mediated by 5-HT(2B) receptors.
Conclusions:
- Gut reflexes are mediated by serotonin (5-HT) secreted by EC cells, acting on intrinsic and extrinsic neurons.
- Dysregulation of 5-HT in the gut contributes to IBS pathogenesis.
- 5-HT plays a vital role in enteric nervous system development, necessitating caution with related drugs during pregnancy.
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