[Formation of superoxide radicals in the mitochondria of skeletal muscle].

The superoxide-dependent oxidation of adrenaline by skeletal muscle mitochondria (maximal inhibition by superoxide dismutase from 50 to 80%) is described. The oxidation reaction is initiated by antimycin A but not by rotenone. It was assumed that the main source of superoxide radicals in skeletal muscle mitochondria is the site of the respiratory chain between the rotenone and antimycin block. It was found that skeletal muscle mitochondria are characterized by a higher rate of superoxide anion formation and by a lower activity of superoxide dismutase as compared to heart mitochondria.