Muscle relaxation pathway

Muscle relaxation is a complex physiological process involving cessation of neural input, repolarization of muscle membranes, active Ca²⁺ reuptake, and regulation of contractile proteins. Therapeutically, "muscle relaxation" is achieved using drugs that act at various molecular sites, most notably the nicotinic acetylcholine receptor at the neuromuscular junction for skeletal muscle blockade (e.g., succinylcholine, rocuronium, vecuronium), and central sites for spasmolytic effects (e.g., GABA receptors, α₂-adrenergic receptors). In smooth muscle, relaxation is regulated by Ca²⁺ signaling, calmodulin, myosin light chain kinase, and myosin phosphatase, as well as endogenous relaxants like nitric oxide[1][2][5][6][7][8][9][10]. The "muscle relaxation pathway" broadly refers to these interrelated molecular cascades and not to a single target, and should not be used as a canonical drug target.

Other names

muscle relaxation mechanismsexcitation-contraction relaxation couplingmuscle relaxant pathway

Blockade or agonism of nicotinic acetylcholine receptor at the neuromuscular junction (depolarizing and non-depolarizing agents); Modulation of GABAergic transmission centrally (spasmolytics); Activation/inhibition of α₂-adrenergic or muscarinic receptors; Modulation of myosin light chain phosphorylation via MLCK and phosphatase