Rat ovarian follicle bioassay reveals adverse effects of cadmium chloride (CdCl2) exposure on follicle development and oocyte maturation

Rat ovarian follicle culture, as a novel bioassay, is adopted in this study to explore the effects of cadmium chloride (CdCL2) on folliculogenesis and oocyte maturation in vitro; the feasibility for its application on detection of possible effects of chemicals on reproduction is discussed and evaluated as well. The results showed that follicle growth, differentiation, and steroidogenesis were significantly disturbed by >= 1.2 mu g/mL CdCl2. The germinal vesicle breakdown of oocyte was also disturbed dose-dependently after the culture follicles were exposed to >= 1.6 mu g/mL CdCl2. Exposure to CdCl2 with concentrations of 1.6 mu g/mL on day 2 had caused significant reduced (p < 0.05) survival rate and rate of antral follicles, and increased abnormal follicle rate significantly, compared to the group exposed on day 6. Rat preantral follicle culture is a potential tool to assess the hazards of chemical compounds on female fertility and can be used to elucidate their mechanisms of actions.