Serotonin 5-hydroxytryptamine receptor 2B and Serotonin 5-hydroxytryptamine receptor 2C (5-HT2B and 5-HT2C)

Serotonin 5-hydroxytryptamine receptors 2B and 2C are subtypes of G protein-coupled receptors that bind serotonin, mediating a range of physiological processes. The 5-HT2B receptor is predominantly expressed in the cardiovascular system, where it regulates cardiac valve structure and vascular tone, and its activation is strongly linked to drug-induced heart valve disease. The 5-HT2C receptor is widely distributed in the central nervous system, where it modulates neurotransmitter release (notably reducing dopamine and norepinephrine), appetite, and influences mood and behavior. Both contribute to signal transduction through Gq/11 activation and are targets for psychoactive and serotonergic drugs. Although structurally and pharmacologically related, the receptors have distinct tissue distributions, functions, and therapeutic risks; hence, while "5-HT2B/2C receptors" is a common grouping in pharmacology, clinically and structurally they are best considered separately for drug development and safety assessment

Other names

5-HT2B receptorSerotonin receptor 2BHTR2B5-HT2C receptorSerotonin receptor 2CHTR2CSerotonin 2B receptor, Serotonin 2C receptor5-HT2B/2C (joint/colloquial reference in literature for drugs affecting both receptor subtypes)

Antagonism: Inhibition of serotonin-mediated signal transduction by blocking the receptor (prevents downstream signaling, e.g., via Gq/11 activation and phospholipase C) - Agonism: Activation of receptor causing downstream signaling (for 5-HT2B, results in smooth muscle contraction and cardiac valve fibroblast proliferation; for 5-HT2C, inhibits dopamine/norepinephrine release) - Inverse agonism or partial agonism: Some drugs display these properties depending on receptor state and ligand