Serotonin receptor 5-hydroxytryptamine 2A receptor, Serotonin receptor 5-hydroxytryptamine 2C receptor, Serotonin receptor 5-hydroxytryptamine 3 receptor (5-HT2A receptor, 5-HT2C receptor, 5-HT3 receptor)

The serotonin (5-hydroxytryptamine, 5-HT) receptors 5-HT2A, 5-HT2C, and 5-HT3 are important members of the serotonin receptor family with distinct structural and functional characteristics. The 5-HT2A and 5-HT2C receptors are G protein-coupled receptors primarily coupled to Gq/11 proteins, leading to activation of intracellular signaling cascades such as phospholipase C, intracellular calcium mobilization, and protein kinase activation. The 5-HT2A receptor is highly expressed in the brain regions involved in cognition, mood, and perception and is the principal mediator of the psychedelic effects of certain hallucinogens. The 5-HT2C receptor is involved in regulating appetite, mood, and gut motility and is a target for anti-obesity drugs and treatment of substance use disorders. The 5-HT3 receptor differs as it is a ligand-gated ion channel responsible for fast excitatory neurotransmission and is a key target of antiemetic drugs. Together these receptors regulate diverse physiological and neurological processes and serve as important therapeutic targets in psychiatric, gastrointestinal, and cardiovascular disorders. The pharmacology of these receptors is complex, involving both canonical G protein pathways and noncanonical signaling, with significant research ongoing to develop selective drugs that maximize therapeutic benefits while minimizing adverse effects.

Other names

5-hydroxytryptamine receptor 2Aserotonin 2A receptor5-hydroxytryptamine receptor 2Cserotonin 2C receptorserotonin type 3 receptor

5-HT2A/2C receptors: coupling to Gq/11 proteins activating phospholipase C (PLC), leading to inositol trisphosphate (IP3) production, intracellular Ca2+ release, protein kinase C activation, and downstream ERK pathway activation. 5-HT2A involved in modulation of Ca2+ currents and signaling cascades relevant to neuroplasticity. 5-HT3 receptor: ligand-gated ion channel mediating rapid cation (Na+, K+, Ca2+) flow upon serotonin binding.