Effect of high pressure oxygen on the steady state of cytochromes in rat-liver mitochondria.
1. The split-beam spectrophotometer was used to monitor changes in the steady state of cytochrome c and cytochromes a+a(3) during pressurization in pure oxygen. 2. High-pressure oxygen was found to cause oxidation of cytochrome c in rat-liver mitochondria, and of cytochromes a+a(3) at low pH. 3. No difference in these effects was found when various substrates were metabolized. 4. Lowering of pH markedly potentiated the high-pressure effect on the cytochromes. 5. Increased temperature and pressure hastened the reaction to high-pressure oxygen. 6. The oxidation of the cytochromes occurs on the substrate side of cytochrome c, probably at the dehydrogenase level, and the time-course of the reaction is compared with effects of oxygen toxicity in vivo.
D000818:Animals; D003580:Cytochromes / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D006931:Hyperbaric Oxygenation; D008099:Liver / Q000166:cytology / Q000378:metabolism*; D008928:Mitochondria / Q000378:metabolism*; D010084:Oxidation-Reduction; D010100:Oxygen / Q000494:pharmacology*; D010101:Oxygen Consumption; D051381:Rats; D013053:Spectrophotometry
D003580:Cytochromes; D010100:Oxygen