丹曲林鈉五水合物抑制劑Dantrolene depresses excitation-contraction coupling in skeletal muscle by binding to the ryanodine receptor 1 and decreasing intracellular calcium concentration. Ryanodine receptors mediate the release of calcium from the sarcoplasmic reticulum, an essential step in muscle contraction. Dantrolene Sodium is the sodium salt form of dantrolene, a hydantoin derivative, and direct-acting skeletal muscle relaxant.