Neuronal alpha-4 beta-2 nicotinic acetylcholine receptor (α4β2 nAChR)

The neuronal alpha-4 beta-2 (α4β2) nicotinic acetylcholine receptor is a pentameric ligand-gated ion channel and the most prevalent nicotinic receptor subtype in the mammalian central nervous system (Wikipedia, 2024; NIH, 2015). It is primarily composed of α4 (encoded by CHRNA4) and β2 (encoded by CHRNB2) subunits, typically arranged in two distinct stoichiometries—(α4)2(β2)3 and (α4)3(β2)2—which differ in their sensitivity to agonists and calcium permeability (GeneCards, 2024; NIH, 2024). This receptor plays a critical role in modulating the release of various neurotransmitters, including dopamine, GABA, and glutamate, thereby influencing cognitive processes such as learning, memory, and attention (NIH, 2022; Patsnap, 2024). Due to its high affinity for nicotine, the α4β2 receptor is the primary mediator of the reinforcing effects of tobacco and is a central target for smoking cessation therapies like varenicline (NIH, 2011; Patsnap, 2024). Beyond addiction, dysfunction or loss of these receptors is associated with neurodegenerative conditions such as Alzheimer's and Parkinson's diseases, as well as certain forms of hereditary epilepsy like Autosomal Dominant Nocturnal Frontal Lobe Epilepsy (ADNFLE) (PLOS, 2013; GeneCards, 2024). Pharmacological targeting of the α4β2 receptor with agonists or positive allosteric modulators is actively being explored to treat cognitive impairment and mood disorders (Patsnap, 2024). However, achieving subtype selectivity is essential to avoid off-target effects on other nicotinic receptors, such as the α3β4 subtype found in autonomic ganglia, which can cause cardiovascular and gastrointestinal side effects (PLOS, 2014).

Other names

Alpha-4 beta-2 nicotinic receptorCHRNA4/CHRNB2 complexalpha4beta2 nAChRNeuronal nicotinic acetylcholine receptor alpha4beta2Cholinergic receptor nicotinic alpha 4 and beta 2 subunits

Agonism, Partial agonism, Positive allosteric modulation, Antagonism