Effect Of Insulin-like Growth Factor-â…¡ On Development Of 2-cell Mouse Embryos In Vitro

[objective] To study the effects of insulin-like growth factor-II on the development of two-cell mouse embryos in vitro, investigate the mechanism of embryogenesis and optimize the culture medium for preimplantation embryos. To provide the theory and experimental bases for optimizing the culture medium of mankind embryos.[Methods] Mouse preimplantation embryos were cultured in the mKSOM media supplemented with IGF-II at different concentrations and divided into five groups: (1)Control: mKSOM medium with no IGF-II; (2) Treatments:4 groups, mKSOM media with 0.1,1,10,100 ng/ml IGF-II respectively. The numbers of blastocyst and hatched blastocyst , and the blastocyst's cell numbers were counted after 96 hours cultured.[Results] 763 two-cell embryos were collected and cultured up to 96 hours. Results:(l) at the time point of 72h culture, blastocyst rates were 94.1%, 92.1%, 91.6%, 88.7% for group 2,3,4,5 respectively. The rates were significantly higher than that (78.4%) of the control(P<0.05);but there was no differention among the four treatments.(2) at 96h point, hatched blastocyst rates were 69.1%, 65.1%, 63.9%, 52.3% respectively in four treatments. The rates of group 2,3,4 were significantly higher than that(42.5%) of the control and the group 5 (P<0.05);but there was no significant (P>0.05) differention between the group 5 and the control; and there was no significant(P>0.05)differention among the rates of group 2,3,4 either. (3) at 96h point, the cell numbers of blastocyst were 69.2±10.8, 75.5 ±11.8, 74.8 ± 11.2, 72.3 ± 12.4 , 69.4 ± 13.2 respectively for the five groups; there was no significant(P>0.05)differention among them.[Conclusion] Among our study range of the concentrations, (1)IGF-II could increase blastocyst rates of two-cell mouse embryos cultured in vitro.(2)It could...