Hydrogen Peroxide (h <sub> 2 </ Sub> O <sub> 2 </ Sub>) Mice 1 - Cell Stage Embryos

To elucidate the mechanism of in vitro developmental block of mammalian early embryos,people have uninterruptedly being investigated embryos arrest reason from both intraembryonic inside and extraembryonic environment ,so far, It has been found that damaged cells contain a wide variety of oxides involving hydrogen peroxide(H2O2) and other some free radicals(such as O-2 and OH-),and that abnormal cells owing to cleavage block and function failure also contain these active oxygen materials.In this experiment, we discuses the reason of the development block of the mouse early embryos and offered the reliable theories for enhancing the developing efficiency of the early embryos of the mammals by investigating the effects of ROS-H₂O₂ on the development of 1-cell embryo of mouse in vitro.We studied the effect of H₂O₂ on 1-cells mouse embryo development in vitro by adding exogenous oxidant-H₂O₂ in different developing periods. The 1-cells embryo was gained from the oviduct of mouse superovulated, and was cultured in vitro. The results of this study show: (1) The blastocyst rate of control group, 1.5 uMol/L group and 1.8 uMol/L group were significantly higher than that of 2.1 uMol/L group,2.4 uMol/L group and 2.6 uMol/L group(p<0.05). (2) The blastocyst rates of both 0¹2h treatment group and 0⁷2h treatment group,which all contained 2.1uMol/L H₂O₂, were significantly lower than that of control group and other groups(P<0.05),and there were not significant difference between 12²4h treatment group,24³6h treatment group,36⁴8h treatment group,48⁶0h treatment group,60⁷2h treatment group.(3)the blastocyst developing rate of both the CZB group and the treatment group not adding 2.1 uMol/L H₂O₂ are significantly higher than those of both the control group and the other treatment groups(P<0.05). and there were not significant difference between 12²4h treatment group,24³6h treatment group,36⁴8h treatment group,48⁶0h treatmentgroup,60⁷2h treatment group and 0⁷2h treatment group.By comparison:,we found that the ROS (such as H₂O₂) can inhibit the development of 1-cellembryos in vitro.and this function is outstanding in the period of development block of embryos. This suggests that the ROS is one of the reasons that induced the development block of the mammalian early embryo.