Effects of Ascorbic Acid and FSH on the Maturation of Mice's Oocytes and Follicles

Progress in laboratory culture conditions for in vitro oocyte maturation has led to development of the treatment of human and animal infertility. In this study we investigated the effects of FSH and ascorbic acid on the in vitro maturation of mouse's follicles and enclosed oocytes. For experiment, intact pre-antral follicles were isolated from the ovaries of 6 week-old female mice and cultured in TCM-199 medium. Special quantities of FSH and ascorbic acid were added to the culture medium (containing 25-30 follicles) during separate experiments: 5, 20, 40, 60, 100, 140, 180 and 220 IU/L of FSH and 20, 40, 80, 240, 300 and 400 nmol/mL of ascorbic acid. Follicles were cultured for 6 days in an incubator at 37 °C, 92% humidity and 5% air CO2. Our study was semi-experimental. The entire statistical analysis was carried out by SPSS (version 14.0 for Windows) using one way ANOVA. Post Hoc tests were used for the multiple comparisons at 95% confidence interval. P values < 0.05 were considered statistically significant. At FSH concentration of 100 IU/L increase in follicle diameter (190µm), survival rate (91%), germinal vesicle breakdown (GVBD) (81%) and oocyte maturation rates (61%) was observed (p ≥0.05). Ascorbic acid increased survival rate (42%, p<0.001) but didn’t affect diameter, GVBD and oocyte maturation rates. Ascorbic acid and FSH-containing medium showed a marked increase in all parameters except for follicle diameter. FSH and ascorbic acid increase the maturation rate of follicles and enclosed oocytes but if they are supplied in a combination, this growth rate can be significantly increased