H2O2 generation in the rat brain in vivo; correlates with oxygen pressure
Yusa, T.
Masui. Japanese Journal of Anesthesiology 35(7): 1077-1082
1986
ISSN/ISBN: 0021-4892 PMID: 3773253 Document Number: 281477
The effect of hyperoxia on the rate of H2O2 generation in the rat brain in vivo was studied. H2O2 generation in vivo was determined by measuring the inhibition of endogenous catalase by aminotriazole. Brain catalase activity in rats breathing air (0.2 ATA O2) decreased 74.95%, 60.91% and 40.26% of the controls at 30, 60 and 120 min. After intaperitoneal aminotriazole injection, respectively. Brain catalase activities in Unit/g, tissue of rats exposed to 0.2 ATA O2 (normobaric air), 0.6 ATA O2 (3.0 ATA air), 1.0 ATA O2 (normobaric 100% O2) and 3.0 ATA O2 for 30 min, were 138.94 .+-. 5.54, 122.75 .+-. 6.25, 120.36 .+-. 4.55 and 94.79 .+-. 3.00 at 30 min, post aminotriazole injection; and 112.91 .+-. 3.70, 104.36 .+-. 2.85, 95.81 .+-. 3.25 and 66.80 .+-. 4.17 at 60 min. post aminotriazole injection, respectively. The calculated relative K(min-1) of H2O2 generation by brain increased directly as a function of oxygen pressure. These findings support the concept that H2O2 and O2-, a precursor of H2O2, are important mediators of oxygen-induced CNS injury.