Gamma-aminobutyric acid and nicotinic acetylcholine receptors (GABA and nAChR)

Gamma-aminobutyric acid (GABA) and nicotinic acetylcholine receptors (nAChRs) are both members of the Cys-loop superfamily of pentameric ligand-gated ion channels (pLGICs) [1]. GABA receptors are the primary mediators of inhibitory neurotransmission in the vertebrate central nervous system, primarily functioning through the GABA-A ionotropic receptor which conducts chloride ions to hyperpolarize neurons [2]. In contrast, nicotinic acetylcholine receptors are excitatory cation channels that respond to the neurotransmitter acetylcholine at the neuromuscular junction and within the autonomic and central nervous systems [3]. While they share structural similarities, such as a pentameric arrangement of subunits, they serve opposing physiological roles and are activated by distinct endogenous ligands [4]. Therapeutically, GABA receptors are targeted by benzodiazepines and anesthetics for sedation and anticonvulsant effects, whereas nAChRs are targeted by drugs for smoking cessation, cognitive enhancement, and surgical muscle relaxation [5].

Other names

GABA receptorsNicotinic acetylcholine receptorsCys-loop ligand-gated ion channelsGABA and nicotinic receptors

Drugs targeting GABA receptors typically act as positive allosteric modulators or agonists to enhance inhibitory tone, while drugs targeting nicotinic acetylcholine receptors act as agonists, partial agonists, or antagonists to modulate excitatory signaling and neuromuscular transmission [2, 3, 5].