Adult muscle-type nicotinic acetylcholine receptor (nAChR)

The adult muscle-type nicotinic acetylcholine receptor (nAChR) is a heteropentameric ligand-gated ion channel located at the postsynaptic membrane of the neuromuscular junction [StatPearls, 2023]. It is composed of two alpha-1, one beta-1, one delta, and one epsilon subunit, a configuration that distinguishes the adult form from the fetal gamma-containing isoform [UniProt, 2024]. The receptor's primary biological role is to mediate neuromuscular transmission by opening an internal pore in response to acetylcholine binding, which allows the flow of cations (sodium, potassium, and calcium) and leads to muscle fiber depolarization and contraction [StatPearls, 2023]. In clinical practice, this receptor is the primary target for non-depolarizing neuromuscular blocking agents like rocuronium, which competitively inhibit acetylcholine binding to induce skeletal muscle relaxation during surgery and intubation [StatPearls, 2023]. Dysfunction of this receptor is also central to autoimmune conditions such as myasthenia gravis, where antibodies target the receptor subunits, leading to impaired transmission and muscle weakness [NIH, 2022].

Other names

Muscle-type nicotinic acetylcholine receptorNeuromuscular nicotinic acetylcholine receptornAChRCHRNAdult-type nAChRAChR

Competitive antagonism of the acetylcholine binding sites on the alpha-1 subunits of the receptor, preventing ion channel opening and subsequent muscle depolarization [StatPearls, 2023].