Serotonin 2A receptor, Serotonin 2B receptor, and Serotonin 2C receptor (5-HT2A, 5-HT2B, and 5-HT2C)

The Serotonin 2A, 2B, and 2C receptors are closely related members of the serotonin (5-hydroxytryptamine, 5-HT) G protein-coupled receptor family, best known for mediating a wide range of CNS and peripheral effects. The 5-HT2A receptor is abundantly expressed in the brain, particularly in regions involved in cognition and sensory perception, and is the main target of classic hallucinogenic/psychedelic drugs, as well as many atypical antipsychotics[1][3][8]. The 5-HT2B receptor plays a critical role in cardiovascular physiology and is infamously linked to cardiac fibrosis and valvular heart disease when overstimulated by certain drugs[8]. The 5-HT2C receptor is involved in modulating mood, appetite, and endocrine secretion, and is implicated in the therapeutic actions and side effects of several neuropsychiatric drugs[3][7]. All three receptors transduce signals primarily through Gq/11 proteins, activating phospholipase C and downstream pathways[5][6]. Abnormal function or regulation of these receptors is implicated in psychiatric, metabolic, and cardiovascular diseases, making them important therapeutic targets for antipsychotic, antidepressant, anti-obesity, and anti-migraine drugs[5][8].

Other names

5-hydroxytryptamine receptor 2A, 2B, 2CHTR2A, HTR2B, HTR2C5-HT2A receptor, 5-HT2B receptor, 5-HT2C receptorSerotonin receptor 2A, 2B, 2C

Agonists: activate Gq/11 pathway, stimulate phospholipase C (PLC), increase IP3 and DAG, raise intracellular Ca2+ and activate PKC. Antagonists: block Gq/11 pathway, inhibit downstream effects, antipsychotic and antidepressant actions (blockade of 5-HT2A, sometimes 5-HT2C). Inverse agonists: suppress constitutive activity of the receptor