Fig. (3) Influence of gossypol on H2O2 generation by mitochondria. Mitochondria (0.8 mg protein/ml) were incubated in a reaction medium containing 0.6 M mannitol, 20 mM Tris-phosphate buffer (pH 7.2), 10 μM CCCP, 20 μM DCDHF-DA and 5 U horseradish peroxidase. Pyruvate and malate were added at a concentration of 5 mM each; succinate, 10 mM; antimycin A, 5 µM; gossypol, 250 µM.