Serotonin 5-hydroxytryptamine receptor 3A (5-HT3A)

The serotonin 5-hydroxytryptamine receptor 3A (5-HT3A) is a subunit of the type 3 serotonin receptor, which is a ligand-gated ion channel. This receptor plays key roles in neurotransmission and is involved in various physiological and pathophysiological processes, including emesis control, cognition modulation, and anxiety regulation. The functional receptor can be formed as a homopentamer of five identical 5-HT3A subunits or as a heteropentamer with other related subunits. Upon binding serotonin, the channel opens to allow cations to flow into neurons, leading to depolarization. Selective antagonists, known as "setrons," are used clinically to prevent chemotherapy-induced nausea/vomiting by blocking this receptor's activity.

Antagonism; stabilization of non-conductive conformational states of the channel that block activation by endogenous ligands like serotonin.