Establishment Of Method To Culture Early Mouse Embryo And Fertilization In Vitro

In vitro fertilization and embryo culture have been widely used in the field of medicine and biology, but they still need further optimize. The purpose of this study is to establish optimal, effective system for in vitro fertilization and embryo culture and advance the quality of embryo. The effects of culture media, sperm of different strains and coculture with somatic cells on early mouse embryo development was evaluate. Especially, the effects of 17β-estradiol on early mouse embryo development were observed.Experiment 1. The results from mouse embro culture and in vitro fertilization showed that zygotes of KM (Kunming Mouse) can be well development in mKSOM medium. The percentages of in vitro fertilization, blastocyst formation and total cell number of blastocyst with the sperm of B6D2F1 (C57BL/6 × DBA/2) were much higher than that with the sperm of KM.Experiment 2. The mouse embryos fertilized in vitro were cocultured with monolayer of mouse uterine epithelial cells, and the effects of coculture were evaluated by the embryo cleavage rate, blastocyst hatched rate and total cell number of blastocyst. The results showed that coculture with uterine epithelial cells can promote the development of early mouse embryos fertilized in vitro.Experiment 3. We investigated the expression of estrogen receptor alpha (ERa) in preimplantation mouse embryos by RT-PCR and immunocytochemistry, and the effects of 17β-estradiol on early embryo development were examined. The results showed that ERa is expressed in early mouse embryos, but the regulation of 17β-estradiol during the early mouse development depends on the uterine epithelial cells.All the results above showed that the method to culture early mouse embryo and fertilization in vitro has been established, and also hint that the regulation of 17β-estradiol during the early mouse development depend on the uterine epithelial cells.