ABSTRACT
The frequency of micronuclei was assessed in polychromatic erythrocytes of bone marrow and normochromatic erythrocytes in peripheral blood of mice following exposure to fenarimol (50, 100, 200 mg/kg b.w.) and nuarimol (100, 200, 400 mg/kg b.w.) for 21 days. Mitomycin С (2 mg/kg b.w.), cyclophosphamide (25 mg/kg b.w.) and colchicyne (2 mg/kg b.w.) were administered to the positive control mice for 5 days. These results obtained in this experiment were compared with the incidence of micronuclei in bone marrow and peripheral blood in mice exposed twice (two consecutive injections, 24 hours interval) to fenarimol and nuarimol and mitomycin C, cyclophosphamide and colchicine. The results show that fenarimol and nuarimol did not cause micronuclei induction in the bone marrow and peripheral blood of mice under the conditions of these experiments. However, mitomycin C, cyclophosphamide and colchicine induced of micronuclei in the investigated tissues. Moreover, the positive relationship between frequencies of micronuclei in normochromatic erythrocytes in peripheral blood and time of exposure was observed.