抄録
Insulin-like growth factor II (IGF-II) is first expressed from the zygotic genome at the two-cell stage of development in mouse embryo. However, the IGF-II is hardly expressed in parthenogenetic embryos because of paternal imprinted gene. In this work, addition of IGF-II (50 ng/ml) to culture medium for preimplantation and post-blastocyst development in vitro stimulated specifically proliferation of inner cell mass (ICM) cells, whereas no effect on mitosis of trophoectoderm (TE) was found. In addition, exogenous IGF-II also contributed to prevent disappearance of ICM during the blastocyst outgrowth in vitro. These results indicate that IGF-II plays an important role for proliferation of ICM cells in not only fertilized embryos but also parthenogenetic embryos.
