A Novel Assay System of Chemicals Using In-vitro Maturation of Mouse Oocytes: Effects of Carbendazim and Griseofulvin

In order to develop an in-vitro assay system for detection of cytogenetic toxicity of chemicals, we cultured mouse oocytes in vitro with two kinds of spindle poisons, carbendazim (MBC) and griseofulvin (GF). When cultured for 15 h with MBC (6 μg/ml), the majority of the oocytes arrested maturation at the metaphase in the first meiosis. This effect of MBC could be achieved with the latter half of the exposure during 15 h for the entire culture. In contrast, a significant proportion of the oocytes cultured with GF (10 μg/ml) could not continue meiosis from the germinal vesicle stage. Therefore, we characterized the difference in the effects of MBC and GF on meiotic progression of mouse oocytes by using this in-vitro assay system, demonstrating that the system would be useful for detection of cytogenetic toxicity of chemicals.