Contribution to the validation of the anaphase-telophase test: Aneugenic and clastogenic effects of cadmium sulfate, potassium dichromate and nickel chloride in Chinese hamster ovary cells

There is increasing evidence that aneuploidy during mitosis may be a factor in the etiology of somatic malignancy The analysis of alterations in anaph ase-telophase of mitosis is a useful test for evaluating the aneuploidogeni c and clastogenic ability of chemicals. Several metals have been found to b e carcinogenic to humans and animals. However, the underlying mechanisms re main unclear. In the present study the aneugenic and clastogenic abilities of cadmium sulfate, potassium dichromate and nickel chloride were analyzed using the anaphase-telophase test. Chinese hamster ovary (CHO) cells cultur ed for two cycles were treated with the desired compound for 8 h before cel l harvesting. The frequency of cells with chromatin bridges. lagging chromo somes and lagging chromosomal fragments was scored. The mitotic index was d etermined by counting the number of mitotic cells per 1,000 cells on each c overslip and was expressed as a percentage of the number of mitotic plates. Statistical comparisons were done using the "G" method. Correlation and re gression analyses were performed to evaluate Variations of the mitotic inde x. Chromium and cadmium were clastogenic and aneugenic and increased the fr equencies of the three types of aberrations scored; nickel had only aneugen ic activity because it increased the frequency of lagging chromosomes. Thes e results indicate that the anaphase-telophase test is sufficiently sensiti ve to detect dose-response relationships that can distinguish clastogenic a nd/or aneugenic activities and that the results obtained using the anaphase -telophase test were similar to those obtained by chromosome counting.