Aneugenic effects of carbendazim and griseofulvin as assayed in the in vitro maturation system of mouse oocytes

To evaluate the aneugenic effects of carbendazim （ MBC ） and griseofulvin （ GF ） on meiosis, we cultured mouse oocytes, allowing them to mature in vitro in the presence of MBC and GF. The incidence of hyperploidy was significantly increased in oocytes cultured with 0.6 µ g/mL or higher concentration of MBC, while the incidence of diploidy was significantly increased in oocytes cultured with 1 or 3 µ g/mL of GF. To investigate the stage-specific effects of these chemicals during meiotic progression, the oocytes were exposed to chemicals for the initial 7 h or final 8 h of the culture. Both MBC and GF were found to effectively induce numerical aberration during the final half of the culture. Thus, in vitro maturation of mouse oocytes is a useful model for the detection of chemically induced aneuploidy and for the detection of stage-specific effects of chemicals during meiosis.