Free radical processes in the rat blood during hyperbaric oxygenation and in the posthyperoxic period

: Effects of prolonged action of low-pressure oxygen (0.3 MPa, 5h) on the free-radical oxidation (FRO) intensity were investigated just after oxygen exposure and 1, 3, 7, days after that. The FRO increase against the background of the anti-radical systems depression was shown by means of blood plasma chemiluminescent analysis. Under these conditions SOD activity and the content of diene conjugates and Schiff's bases increase in erythrocyte membranes. The displacement of equilibrium between pro- and antioxidants and antioxidants contents towards the latter took place in blood plasma on the 1st day after oxygen exposure. The erythrocyte SOD activity was raised while catalase activity was diminished. The last one was accompanied with the decrease in erythrocyte membrane diene conjugates amount. The secondary blood plasma and erythrocyte membrane FRO elevation was observed on the 3rd day after the exposure and, it was held on the 7th day after hyperoxia. The FRO increase in post-hyperoxia period was established.