Nicotinic acetylcholine receptor α4β2 (human) (α4β2 nAChR)

Nicotinic acetylcholine receptor α4β2 is the most abundant neuronal nicotinic receptor subtype in the human brain, comprising two α4 and three β2 subunits (or alternatively three α4 and two β2 subunits), forming a pentameric ligand-gated ion channel. It mediates fast excitatory neurotransmission by increasing membrane permeability to Na^+^ and K^+^ ions upon acetylcholine or nicotine binding, playing crucial roles in neurophysiological processes such as attention, memory, and reward. This receptor is the primary molecular target of nicotine in the brain, underpinning its addictive properties. Disruption of α4β2 nAChR function is linked to nicotine addiction, certain forms of epilepsy, and may play a role in neurodegenerative diseases like Parkinson's disease. Drugs targeting this receptor act as either agonists (stimulating the receptor), partial agonists (inducing submaximal responses), or antagonists (inhibiting function), with therapeutic and diagnostic applications as well as significant safety and dependency concerns[1][2][3][4][5][7][8].

Other names

Alpha-4 beta-2 nicotinic receptorα4β2 nicotinic receptorCHRNA4-CHRNB2 receptorα4β2* nAChR (asterisk indicates possible inclusion of accessory subunits)

Agonist (e.g., nicotine, varenicline) binding leads to channel opening and sodium/potassium influx Partial agonism (e.g., varenicline) resulting in moderate activation and desensitization Antagonists (e.g., mecamylamine, DHβE, certain antibiotics) block or inhibit channel function