Enhancement of DMA Chain Breakage by Bleomycin A2 in the Presence of Microsomes and Reduced Nicotinamide Adenine Dinucleotide Phosphate1
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چکیده
Chain breakage in DMA induced by bleomycin A (BLM) was enhanced more than 150-fold by the reduced nicotinamide adenine dinucleotide phosphate-dependent elec tron transport system of rat liver microsomes. However, the enhancement effect on DMA was partially reduced by the preincubation of BLM with the microsomal systems. BLM-Cu2' was found to stimulate considerably micro somal reduced nicotinamide adenine dinucleotide phos phate-dependent oxygen consumption and malondialdehyde formation, whereas BLM inhibited both of the ef fects. These findings suggest that the pharmacological action of BLM is strongly affected by a membrane system, such as microsomes, that produces free radicals.
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