TY - JOUR T1 - THE MECHANISM OF ACTION OF RYANODINE ON SKELETAL MUSCLE JF - Journal of Pharmacology and Experimental Therapeutics JO - J Pharmacol Exp Ther SP - 477 LP - 486 VL - 121 IS - 4 AU - Jacob J. Blum AU - Richard Creese AU - Donald J. Jenden AU - Norman W. Scholes Y1 - 1957/12/01 UR - http://jpet.aspetjournals.org/content/121/4/477.abstract N2 - An attempt has been made to determine the site and mechanism of action of ryanodine in skeletal muscle, where it causes an irreversible contracture. Evidence is presented that it does not act at the neuromuscular junction and that the resting membrane potential of muscle is unaffected. It does not alter the ATPase activity or the light scattering response of Myosin B to ATP or the ATP induced shortening of glycerol-treated muscle fibers. The existence of a latent period before the development of contracture, the duration of which is inversely related to the concentration of ryanodine, together with other evidence, suggests that the characteristic action of ryanodine may result from the progressive inactivation or destruction of a key entity necessary for contraction and relaxation. ER -