بررسي اثر نور بر تكوين جنين هاي مرحله قبل از لانه گزيني موش در محيط آزمايشگاه

The Effect of Light on Mouse Preimplantation Embryo Development in Vitro

Background and purpose: In assisted reproductive (ART) laboratory, during the experimental manipulation, oocytes and early embryos are exposed to day light or artificial light for variable periods. The purpose of this study was to assess the effect of fluorescent light exposure, with intensity almost equal to that produced by microscopes in ART laboratory, on mouse early embryo development. Materials and methods: The bicellular embryos were obtained from superovulated pregnant female NMRI mice 48 hours after HCG injection. After washing, the embryos were randomly allocated in HEPES buffered HTF medium into three experimental and one control group. Two hundred and fifteen (group B), 222 (group C) and 229 (group D) bicellular embryos were exposed to fluorescent light of 800 LX for 5, 10 and 30 minutes at 37°C, respectively. The embryos of control group (215, group A), and also other groups (B, C and D) were kept on a heat plate during the time of experiment and protected from the light by covering the dishes with aluminium foil. Expanding and hatching blastocyst rates were recorded after 72 and 96 hours of culture, respectively. Results: The results demonstrated that 61.6%, 52.5% and 65.1% of embryos in the experimental groups (group B, C, and D respectively) and 61% of embryos in the control group reached to blastocyst stage. There was no statistically significant difference between the experimental and the control groups. Also the hatching rates and degeneration rates showed no significant differences between the groups. Conclusion: The fluorescent light of 800 LX for a period of less than 30 minutes had no significant effect on mouse embryo development in vitro.