[Interrelationship between the generation of oxygen anion-radicals and the reduction of artificial acceptors and cytochrome P-450 by NADPH-cytochrome c reductase].
The interaction of NADPH-cytochrome c reductase with oxygen, artificial acceptors and cytochrome P-450 is investigated. It is found that generation of oxygen anion-radicals (O2-), determined from the reaction of adrenaline oxidation into adrenochrome, proceeds independently on the reactions of interaction with artificial "anaerobic" acceptors-cytochrome c, dichlorophenolindophenol. Propylgallate competitively inhibits the reaction of adrenaline oxidation by isolated DADPH-cytochrome c reductase and non-competitively suppress the reaction of cytochrome c reduction. In contrast to the process of electron transfer on cytochrome c, there is a direct correlation between the rate of cytochrome P-450 reduction and the rate of adrenaline oxidation in liver microsomes. Hexobarbital increases V of the adrenaline oxidation reaction and does not affect the Km value, while metirapon, a metabolic inhibitor, decreases the Vmax and does not change Km. On the basis of the data obtained it is suggested that the reactions of NADPH-cytochrome c reductase interaction with oxygen and artificial "anaerobic" acceptors are connected with different redox-states of flavoprotein or with different flavine coenzymes, and that the electron transport on cytochrome P-450 and directly on oxygen takes place in interrelated redox-states of flavoprotein.
D015086:2,6-Dichloroindophenol / Q000378:metabolism; D000693:Anaerobiosis; D000818:Animals; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism*; D003579:Cytochrome Reductases / Q000378:metabolism*; D003574:Cytochrome c Group / Q000378:metabolism; D004579:Electron Transport; D004837:Epinephrine / Q000378:metabolism; D005609:Free Radicals; D007700:Kinetics; D008862:Microsomes, Liver / Q000201:enzymology*; D009251:NADPH-Ferrihemoprotein Reductase / Q000037:antagonists & inhibitors / Q000378:metabolism*; D010084:Oxidation-Reduction; D010100:Oxygen; D051381:Rats; D013329:Structure-Activity Relationship
D003574:Cytochrome c Group; D005609:Free Radicals; D003577:Cytochrome P-450 Enzyme System; D015086:2,6-Dichloroindophenol; D003579:Cytochrome Reductases; D009251:NADPH-Ferrihemoprotein Reductase; D010100:Oxygen; D004837:Epinephrine
Vzaimosviaz' mezhdu generatsiei anion-padikalov kisloroda i vosstanovlennem iskusstvennykh aktseptorov i tsitokhroma P-450 Nadph-tsitokhrom-c-reduktazoi.