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Cadenas E, Boveris A, Chance B: Low-level chemiluminescence of bovine heart submitochondrial particles. Biochem J. 1980 Mar 15;186(3):659-67.
Submitochondrial particles from bovine heart mitochondria showed low-level chemiluminescence when supplemented with organic hydroperoxides. Chemiluminescence seems to measure integratively radical reactions involved in lipid peroxidation and related processes. Maximal light-emission was about 1500 counts/s and was reached 2-10min after addition of hydroperoxides. Ethyl hydroperoxide, cumene hydroperoxide and t-butyl hydroperoxide were effective in that order. Antimycin and rotenone increased chemiluminescence by 50-60%; addition of substrates, NADH and succinate did not produce marked changes in the observed chemiluminescence. Cyanide inhibited chemiluminescence; half-maximal inhibitory effect was obtained with 0.03mm-cyanide and the inhibition was competitive with respect to t-butyl hydroperoxide. Externally added cytochrome c (10-20mum) had a marked stimulatory effect on chemiluminescence, namely a 12-fold increase in light-emission of antimycin-inhibited submitochondrial particles. Stimulation of hydroperoxide-induced chemiluminescence of submitochondrial particles by cytochrome c was matched by a burst of O (2) consumption. O (2) is believed to participate in the chain radical reactions that lead to lipid peroxidation. Superoxide anion seems to be involved in the chemiluminescence reactions as long as light-emission was 50-60% inhibitible by superoxide dismutase. Singlet-oxygen quenchers, e.g. beta-carotene and 1,4-diazabicyclo [2,2,2]-octane, affected light-emission. beta-Carotene was effective either when incorporated into the membranes or added to the cuvette. The present paper suggests that singlet molecular oxygen is mainly responsible for the light-emission in the hydroperoxide-supplemented submitochondrial particles. |
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