Abstract: BACKGROUND AND AIM: To explore the effect of thioglycolic acid(TGA) on mouse ovulation and in vivo maturation of oocytes. MATERIALS AND METHODS: Kunming mice were used in this study. In each experiment twelve mice were allocated to four groups,control, 37.812 5, 75.62 5 and 151.25 mg/kg TGA groups. The mice received various doses of TGA percutaneously, and intraperitonea 10 IU human chorionic gonadotrophin simultaneously 14 hours later the number of ovulated oocytes was counted. Immunofluenscence staining was used to label spindle and cortical granule (CG) in the matured oocytes. RESULTS: Compared to the control, only 151.25 mg/kg TGA group showed significantly decreased ovulated oocytes(P<0.01), and also significantly lower than that in 37.812 5 mg/kg group(P<0.05). The spindle in control and 37.812 5 mg/kg groups were bipolar, but had a barrel configuration in 75.625 mg/ml and 151.25 mg/ml groups. The area of spindle increased with increasing TGA dose. TGA had no significant influence on the distribution of CGs and the formation of cortical granule-free domain(CGFD). CONCLUSION: Percutaneous administration of TGA inhibited ovulation of mouse and inhibited oocyte maturation in vivo.

Key words: thioglycolic acid, oocyte, spindle, cortical granule, ovulation