Dose response curve for micronucleus of cytokinesis-block method in human lymphocytes after 60Co-gamma ray exposure

The micronucleus technique of cytokines block has been proposed as a new method to measure chromosome damage in cytogenetic. The cytokines is blocked by using cytochalasin B (Cyt-B), and micronuclei are scored in cytokines-blocked (CB) cells. This can easily be done owing to the appearance of binucleate cells and large numbers accumulated by adding 3.0 μg/ml cytochalasin B at 44 hours and scoring at 72 hours. The results show that the optimum concentration of Cyt-B is 3.0 μg/ml. the Cyt-B itself can not induce the increase of micronuclei. The micronucleus frequency of normal individuals in vivo, there is an approximately linear relationship between the frequency of induced micronuclei and irradiation dose. The formula is Y 0.36 D + 2.74 (γ2 = 0.995 P<0.01). Because the cytokines block method is simple and reliable, it is effective for assaying chromosome damage caused by genetic toxic materials