Nematode somatic muscle nicotinic acetylcholine receptor (nAChR)

Nematode somatic muscle nicotinic acetylcholine receptors (nAChRs) are pentameric ligand-gated ion channels that play a fundamental role in the locomotor system of nematodes by mediating excitatory neuromuscular transmission (Martin et al., 2012, PubMed). These receptors are located on the muscle cells and respond to the neurotransmitter acetylcholine by opening a cation-selective pore, which leads to muscle depolarization and contraction (Richmond, 2005, WormBook). In parasitic nematodes, these receptors are the primary targets for several major classes of anthelmintic drugs, including imidazothiazoles (e.g., levamisole) and tetrahydropyrimidines (e.g., pyrantel). These drugs act as potent agonists, causing prolonged activation of the receptors that results in spastic paralysis and the subsequent expulsion of the worm from the host (Robertson et al., 2013, British Journal of Pharmacology). There are distinct subtypes of these receptors, such as the levamisole-sensitive (L-type) and nicotine-sensitive (N-type), which differ in their subunit composition and pharmacological sensitivity (Boulin et al., 2008, Nature). Antagonists like derquantel also target these receptors but induce flaccid paralysis by blocking cholinergic signaling (Little et al., 2011, International Journal for Parasitology). The development of resistance to these drugs, often through mutations in receptor subunits like UNC-38 or UNC-29, poses a significant challenge to the control of parasitic infections in both human and veterinary medicine (Kopp et al., 2007, Trends in Parasitology).

Other names

L-type nicotinic acetylcholine receptorN-type nicotinic acetylcholine receptorLevamisole-sensitive nAChRNicotine-sensitive nAChRNematode muscle nAChRL-nAChRN-nAChRLevamisole receptor

Anthelmintic agonists (e.g., levamisole, pyrantel) produce a persistent activation of the receptor, leading to a depolarizing neuromuscular block and spastic paralysis of the nematode (Martin et al., 2012, PubMed). Antagonists (e.g., derquantel) bind to the receptor and prevent acetylcholine from inducing depolarization, resulting in flaccid paralysis (Little et al., 2011, International Journal for Parasitology).