Serotonin 5-hydroxytryptamine receptor 2A (5-HT2A receptor)

The **Serotonin 5-hydroxytryptamine receptor 2A** (5‑HT₂A) is a member of the class A G protein-coupled receptors that mediates many central nervous system effects of serotonin. It is widely expressed in the brain, especially in cortical regions involved in cognition, mood regulation, and perception. The structure features seven transmembrane α-helices forming a dynamic ligand-binding pocket that accommodates both endogenous neurotransmitters like serotonin as well as exogenous hallucinogens such as LSD and psilocin. Activation leads to coupling with Gq proteins, triggering phospholipase C activation and subsequent intracellular calcium release. The receptor plays a key role in neuropsychiatric conditions including schizophrenia and depression; it is also the primary molecular target for classic psychedelic drugs. Numerous antipsychotics act as antagonists at this site. Its complex pharmacology makes it an important therapeutic target but also presents challenges regarding side effects such as hallucinations or cardiovascular risks depending on drug selectivity profiles[1][3][4].

Other names

5-HT2A receptorSerotonin receptor 2AHTR2A (gene symbol)5-hydroxytryptamine receptor 2A

Agonism at the serotonin binding site triggers intracellular Gq/11 protein signaling cascades leading to increased intracellular calcium and activation of downstream effectors[1][3]. – Antagonism or inverse agonism blocks or reduces this pathway.