Studies of the effect of superoxide dismutase and chemical radioprotectors (cysteine and glutathione) on radiation-induced changes in the DNA molecule. 1

Melting curves and destruction of nitrogen bases were investigated for irradiated DNA preparations isolated from calf thymus. DNA solutions were subjected to γ radiation from a 60Co source [Gamma-Cell 86 krad/h] in the range of doses 10 - 50 krad. Radioprotective effect of superoxide dismutase was studied and compared with the effects of chemical radioprotectors (cysteine and glutathione). The obtained results evidence statistically significant radioprotection by cysteine and glutathione. It was not possible to demonstrate the protective effect of superoxide dismutase due to its specific enzymatic action. (author)