Document Type : Original Article
Introduction: In this study in vitro maturation, resumption of meiosis and development of immature mouse oocytes in the presence of cysteamine was evaluated.
Meterial and Methods: Immature oocytes recovered from NMRI mouse strain (4-6 weeks) were categorized in three experimental and one control group. The control included 345 immature oocytes which were matured in MEM medium contain 5% FCS. In group one 292 immature oocytes were matured MEM medium contain 5% FCS and 100 m cysteamine. In the second group 237 immature oocytes were matured in MEM medium contain 5% FCS, 7.5IUhcG, 100mIUrFSH and in the third group 264 immature oocytes were matured in MEM medium contain 5% FCS, 7.5IUhcG, 100mIUrFSH, 100 m cysteamine. Fertilization and embryo development were performed in T6 medium.
Results: The percentage of resumption of meiosis and IVM in control and the three experimental groups were 74.2, 99.2, 74.24, 85.6 and 59.7, 81.2, 52.74, 85.6 respectively. Statistically significant difference was seen regarding in vitro maturation and resumption of meiosis between control and experimental group 1 and group 3 (P=0.0001). The embryo formation in group 1 and group 3 was higher compared to the other groups (without cysteamines). The embryo formation after 24 hours in group 1 (P=0.0001) and group 3 (0.0001) increased significantly compared to the second group.
Conclusion: The result of this study showed that cysteamine (100 m) enhances in-vitro maturation, resumption of meiosis and has no significant effect on embryo development.