Reduction of 1-nitroso-2-naphthol by NADPH in the presence of liver microsomes.
1. The endogenous, NADPH-supported production of H2O2 and of O2-.-radicals in liver microsomes, was very strongly enhanced in the presence of 1-nitroso-2-naphthol. 2. A 30-fold induction by NON was the consequence of its direct reduction to NON-radicals, catalyzed by microsomal NADPH:cytochrome P450 reductase. 3. Nitroso radicals reduce molecular oxygen to superoxide anion radicals, which were readily dismutated by superoxide dismutase to hydrogen peroxide. 4. O2-.-radicals were the sole precursors of all NON-induced production of H2O2 in liver microsomes.
Faculty of Technology, Bulevar AVNOJa, Novi Sad, Yugoslavia.
V
V
Leskovac
J O
JO
Peggins
S
S
Trivić
J
J
Svircević
M
M
Popović
M
M
Stupar
D000818:Animals; D005609:Free Radicals; D006861:Hydrogen Peroxide / Q000378:metabolism; D008297:Male; D008862:Microsomes, Liver / Q000201:enzymology*; D009243:NAD / Q000378:metabolism; D009249:NADP / Q000378:metabolism*; D009251:NADPH-Ferrihemoprotein Reductase / Q000378:metabolism; D009603:Nitroso Compounds / Q000378:metabolism*; D010084:Oxidation-Reduction; D051381:Rats; D017207:Rats, Sprague-Dawley; D013482:Superoxide Dismutase / Q000378:metabolism; D013481:Superoxides / Q000378:metabolism
D005609:Free Radicals; D009603:Nitroso Compounds; D009243:NAD; D013481:Superoxides; D009249:NADP; C025341:1-nitroso-2-naphthol; D006861:Hydrogen Peroxide; D013482:Superoxide Dismutase; D009251:NADPH-Ferrihemoprotein Reductase