Serotonin is a monoamine neurotransmitter in the CNS and an endogenous 5-HT receptor agonist. Serotonin is also a catechol O-methyltransferase (COMT) inhibitor with a Ki of 44 μM.

Serotonin is a monoamine neurotransmitter in the CNS and an endogenous 5-HT receptor agonist. Serotonin also inhibits catechol O-methyltransferase (COMT), an enzyme that contributes to modultion the perception of pain, via non-competitive binding to the site bound by catechol substrates with a binding affinity comparable to the binding affinity of catechol itself (Ki= 44 μM). Results show that addition of 100 μM of Serotonin decreases the reaction velocity of COMT[1].

Serotonin produces robust hypersensitivity compare to saline-treated controls (p<0.001)[1]. A significant increase in colonic 5-HT content is observed in IL-13-/- mice receiving Serotonin compare to IL-13-/- receiving vehicle following induction of DSS colitis[2].

[1]. Tsao D, et al. Serotonin-induced hypersensitivity via inhibition of catechol O-methyltransferase activity. Mol Pain. 2012 Apr 13;8:25.
[2]. Shajib MS, et al. Interleukin 13 and serotonin: linking the immune and endocrine systems in murine models of intestinal inflammation. PLoS One. 2013 Aug 28;8(8):e72774.