Hydrazine radical formation catalyzed by rat microsomal NADPH-cytochrome P-450 reductase

Using NADPH-cytochrome P-450 reductase purified from rat liver microsomes, the oxidation of hydrazine to its radical was proved to proceed smoothly. The catalytic effect of NADPH cytochrome P-450 on the radical formation in the hepatic microsomes obtained from phenobarbital-pretreated rats was also supported by the fact that Hz radical formation was stimulated by flavin adenin dinucleotide or methyl viologen and markedly inhibited by superoxide dismutase, however, carbon monoxide showed no effect. Expectedly, anti-NADPH-cytochrome P-450 IgG decreased the radical formation. The present study provides the first evidence for the NADPH-cytochrome P-450 reductase catalyzed oxidation of hydrazine to its radical in the presence of O2 and NADPH.