[Effect of vanadate on Ca++-activation in skeletal muscle].
Vanadate (0.1 mM) reduces tension of glycerinated rabbit psoas muscle fibers, shifts tension--pCa curve to lower pCa, increases the rate constant of delayed tension development and changes dependence of this rate constant on the level of Ca2+-activation. Vanadate influence stops the increase of the rate constant with the rise of Ca++-activated tension. Since actin-myosin-ADP complex is dissociated by vanadate, the muscle performance at low activation levels is supposed to be conditioned largely by the cross-bridges interacting with actin of the actin blocks switched on by myosin-ADP. Kinetics of such cross-bridges differs from that of the cross bridges interacting with actin activated by Ca++ binding to troponin C.
D000199:Actins / Q000378:metabolism; D000244:Adenosine Diphosphate / Q000378:metabolism; D000818:Animals; D002118:Calcium / Q000494:pharmacology*; D005990:Glycerol / Q000494:pharmacology; D007700:Kinetics; D009119:Muscle Contraction / Q000187:drug effects*; D009132:Muscles / Q000187:drug effects / Q000502:physiology; D009218:Myosins / Q000378:metabolism; D011817:Rabbits; D014638:Vanadates; D014639:Vanadium / Q000494:pharmacology*
D000199:Actins; D014639:Vanadium; D014638:Vanadates; D000244:Adenosine Diphosphate; D009218:Myosins; D005990:Glycerol; D002118:Calcium
Vliianie vanadata na Ca2+-aktivatsiiu skeletnoĭ myshtsy.