Neuronal nicotinic acetylcholine receptor α4β2 (α4β2 nAChR)

The neuronal nicotinic acetylcholine receptor α4β2 is a pentameric ligand-gated ion channel composed of α4 and β2 subunits arranged in either 3α:2β or 2α:3β stoichiometries. It is the principal high-affinity receptor for nicotine in the human brain and plays a crucial role in synaptic transmission, chiefly by mediating excitatory signaling through increased influx of sodium and efflux of potassium ions. The α4β2 receptor is widely distributed in the central nervous system and underlies key processes including learning, memory, reward, and the addictive properties of nicotine. Pharmacological modulation of α4β2 nAChRs—through agonists, partial agonists, or antagonists—is integral to therapies for nicotine addiction, cognitive disorders, and selected neuropsychiatric conditions. Receptor structure and drug interaction characteristics are well-resolved, allowing for targeted drug development and selectivity. Genetic variants affecting this receptor are implicated in height, obesity, and familial epilepsy syndromes. Safety concerns include the risk of addiction, seizures, and neuropsychiatric effects, but the receptor largely remains a prime target for CNS therapeutics and diagnostic imaging.

Other names

Alpha-4 beta-2 nicotinic receptorα4β2 receptorCHRNA4/CHRNB2 receptor (gene-based notation)Neuronal α4β2 nicotinic receptor

Agonists: Activate the receptor, leading to increased Na⁺ and K⁺ permeability and neuronal excitation Partial agonists: Bind with lower efficacy for modulating receptor activity (e.g., varenicline for smoking cessation) Antagonists: Block the receptor, preventing activation (e.g., mecamylamine)