[Kinetic properties of the Ca2+--ATPase in the skeletal muscle sarcolemma of the rabbit normally and in E-avitaminotic dystrophy]

Abstract

The article deals with values of seeming Michaelis' constants (for ATP) obtained at different temperatures and Michaelis' constants (for Ca ATP) obtained at 30degrees C with pathology and in norm for sarcolemma Ca2+-ATPase. It follows from the analysis of the Ca2+ total concentration effect (the ATP total concentration being constant) on the activation energy of ATP hydrolysis reactions that with pathology sarcolemma possesses, evidently, a greater adsorption affinity to Ca2+ (the enzyme activator) than in norm. The thermoinactivation properties of the enzyme are studied. It is shown that the inactivation coefficient with pathology increases more rapidly with a temperature rise than in norm. It indicates to the fact that the enzyme from the dystrophic muscles is more labile to the heat effect than from the normal ones.