Superoxide dismutase activity in radioresistant tissues of irradiated rabbits

The activities of Cu, Zn-containing superoxide dismutase were studied in radioresistant tissues (liver, brain, erythrocytes) of whole-body irradiated rabbits with 6.0 Gy and 24.0 Gy with local shielding. No significant changes were observed after irradiation with 6.0 Gy. Both the changes in Cu, Zn-SOD activity and the protein concentrations were more pronounced after exposure to 24.0 Gy with local shielding of the head and abdominal region. The dose on the shielded regions was about 6.0 Gy. Local shielding of rabbits irradiated with a lethal dose 24.0 Gy influenced positively the survival of animals. However, the decrease in SOD activity on 60th day after irradiation seems to be unfavourable for further survival of rabbits, if we accept that SOD content in tissue is maintained at a rather constant level.