Serotonin 3 Receptor (5-HT3 receptor)

The 5-HT3 receptor is a ligand-gated ion channel that belongs to the Cys-loop superfamily. It's a cation-selective channel permeable to Na⁺ and K⁺, mediating fast excitatory neurotransmission. It is formed as a pentamer, either as a homopentamer of five identical 5-HT3A subunits or as heteropentamers combining the A subunit with one or more B, C, D, or E subunits. It is primarily known for its role in emesis and is targeted by "setron" antiemetics but is also implicated in pain, psychiatric, and gastrointestinal disorders.

Other names

5-hydroxytryptamine type-3 receptorHTR3AHTR3BHTR3CHTR3DHTR3E

Cation-selective channel permeable primarily to Na⁺ and K⁺ ions. Activation leads to rapid neuronal depolarization/excitation in both central and peripheral nervous systems by allowing cations to flow into neurons upon serotonin binding. Antagonists block this ion flow.