Abstract
The presence of the H(2) S pathway in skeletal muscle (SKM) has recently been established. SKM expresses the three constitutive H(2) S-generating enzymes in animals and humans, and it actively produces H(2) S. The main, recognized molecular targets of H(2) S, that is, potassium channels and PDEs, have been evaluated in SKM physiology in order to hypothesize a role for H(2) S signalling. SKM dysfunctions, including muscular dystrophy and malignant hyperthermia, have also been evaluated as conditions in which the H(2) S and transsulfuration pathways have been suggested to be involved. The intrinsic complexity of the molecular mechanisms involved in excitation-contraction (E-C) coupling together with the scarcity of preclinical models of SKM-related disorders have hampered any advances in the knowledge of SKM function. Here, we have addressed the role of the H(2) S pathway in E-C coupling and the relative importance of cystathionine β-synthase, cistathionine γ-lyase and 3-mercaptopyruvate sulfurtransferase in SKM diseases.