Effect of vinblastine sulfate on gamma-radiation-induced DNA single-strand breaks in murine tissues

The effect of vinblastine sulfate on gamma-radiation-induced DNA strand breaks in different tissues of tumour bearing mice, was studied by single-cell gel electrophoresis. Intraperitonial administration of different doses (0.25-2.0mg/kg body weight) of vinblastine sulfate 30 min prior to 4 Gy gamma-radiation exposure showed a dose-dependent decrease in the yield of DNA strand breaks in murine fibrosarcoma, blood leukocytes and bone marrow cells. The dose-dependent protection of cellular DNA against radiation-induced strand breaks as evidenced from comet tail length, tail moment and percent DNA in the tail, was more pronounced in bone marrow cells than in the cells of the tumor fibrosarcoma. In fibrosarcoma cells, the decrease in comet tail length, tail moment and percent DNA in the tail was detected at lower doses of vinblastine sulfate administration and these parameters were not significantly altered at higher doses, from that of the control irradiated. From this study, it appears that in addition to anticancer activity, vinblastine sulfate could offer protection to the normal tissues against gamma-radiation-induced DNA strand breaks.