Inhibition of mitochondrial oxidative phosphorylation by adriamycin

The antitumour antibiotic, adriamycin, inhibited oxidative phosphorylation in freshly prepared mitochondria from the heart, liver and kidney of the rat. It abolished respiratory control and stimulated ATPase activity. Succinate oxidation by heart mitochondria was extremely sensitive to the drug when hexokinase was present in the reaction medium. The sensitive site has been identified to lie in the region between the succinate dehydrogenase flavoprotein and ubiquinone of the respiratory chain.