Aneugenic effects of some metals compounds assessed by chromosome counting in MRC-5 Human Cells

GÜERCI, A.M; A.I. SEOANE AND F.N. DULOUT.

MUTATION RESEARCH. GENETIC TOXICOLOGY AND ENVIRONMENTAL MUTAGENESIS

Elsevier Science B.V

Lugar: Leiden. Netherland; Año: 2000 vol. 469 p. 35 - 40

1383-5718

Development of a comprehensive test battery is necessary for the evaluation and detection of aneugenic chemicals. The chromosome counting method was used in the present study. The aneugenic ability of cadmiun chloride (1.0, 2.0 and 4.0 x 10 –3 mM), cadmiun sulfate (3.3, 6.7 x 10 –5, and 1,3 10 –4 mM) were analysed using MRC-5 cells which have a modal diploid number of 2 n=46 with a spontaneous aneuploid or polyploid cells no higher than 13 % and 8 %, respectively.  All compounds induced significant increments of aneuploid cells in relation to negative controls. The frequency of aneuploid cells increased in all treatments with cadmiun chloride. Cadmiun sulfate induced significant increments  of aneuploidid cells with  the two higher doses. All the doses of potassium dichromate increased the frequency of aneuploid cells although to a lesser degree than the other compound. In these cases, differences were in the boderline of statistical significance (p<0.05). Moreover, a low number of cells could be analysed in treatments with the highest dose due to the decrease in the mitotic index. Results obtained are coincident with previous reports using the same methodology in the sense that induced aneuploidy was mainly evidenced by the increased of hypodiploid but not hyperdiploid cells. In addition, anaphase-telophase analysis of the effects of the same doses of these metal coumpounds in CHO cells showed significant increments of lagging chromosomes and increased frequencies of kinetochore positive micronuclei in MRC-5 cells. These findings could be considered as an indication that the main cause of unequal chromosome separation  is the failure of kinetochores to attach the spindle apparatus either by alteration of its protein components or by  the altered chromatid separation in anaphase.