Serotonin 5-hydroxytryptamine-3 receptor (5-HT3 receptor) (5-HT3 receptor)

The Serotonin 5-hydroxytryptamine-3 (5-HT3) receptor is a member of the Cys-loop family of ligand-gated ion channels, distinguishing it from all other serotonin receptors which are G protein-coupled receptors [1, 2]. It is a pentameric structure composed of various subunits (5-HT3A-E) that form a central pore permeable to cations like sodium, potassium, and calcium [1, 3]. These receptors are strategically located in the peripheral nervous system on vagal afferents and in the central nervous system within the area postrema and nucleus tractus solitarius, where they mediate the vomiting reflex [2, 4]. In the gut, 5-HT3 receptors regulate intestinal motility and fluid secretion, making them key players in the pathophysiology of irritable bowel syndrome [4, 5]. Pharmacological modulation of these receptors, primarily through competitive antagonism, is a cornerstone in the management of chemotherapy-induced and postoperative nausea and vomiting [2, 6]. Additionally, research suggests the receptor's involvement in sensory processing, anxiety, and cognitive functions, highlighting its potential as a target for diverse neuropsychiatric conditions [3, 5].

Other names

5-HT3R5-hydroxytryptamine receptor 3Serotonin-gated ion channelHTR3

Antagonism of the 5-HT3 receptor inhibits the activation of the vagus nerve and the chemoreceptor trigger zone, thereby preventing the emetic response and slowing colonic transit time.