自分泌生长因子对早期胚胎体外发育的影响(简报)

THE EFFECT OF AUTOCRINE FACTORS ON DEVELOPMENT OF EARLY EMBRYOS OF MOUSE

生长因子(Growth Factors,GFs)对于调节哺乳动物胚胎的早期发育和分化起着重要作用,这些GFs存在于雌性生殖道,也可由胚胎自身合成[1].正是由于这种自分泌GFs的存在,使我们可以通过改变胚胎培养密度或添加外源性GFs来定性或定量研究GFs对胚胎发育和分化的影响,对于了解GFs在分子水平上的作用途径和机制有着重要的意义.

Two-cell-stage embryos were flushed from the oviducts on Day 2. Zygotes were collected from oviducts on Day 1 (Fertilization In Situ, ISF) or derived from fertilization in vitro (IVF). 2-cell embryos had a high rate of blastocyst development to each embryo concentration from 1 embryo/μl to 1 embryo/1000 μl. The zygotes produced by either ISF or IVF were adversely affected by reducing the embryo concentration over this range (P<0. 001), with approximately 82. 5 % of ISF zygotes developing to blastocysts at highest concentration but only 22. 3% at the lowest. For IVF zygotes the corresponding results were 46. 3 % and 5.2%. The number of cells in each blastocyst from 2-cell embryos was significantly higher than that from ISF and IVF group. The media supple- menting Platelet-activating factor (PAF) caused a significant increase in the rate of blastocyst development of IVF zygotes at embryo concentration of 1 embryo/10 μl (10ng/ml) and 1 embryo/100 μl (100ng/ml). Insulin-like growth factor (IGF) (10ng/ml) also stimulated development of IVF zygotes when they were cultured at the concentration of 1 embryo/10μl. Epidermal growth factor (EGF) was no effect over range of 1 - 1000 ng/ml to embryo development. The results show that factors necessary for normal embryo development are diluted to suboptimal levels during culture at low embryo concentration. The PAF, IGF-1 partially compensate the effects of low embryo concentration during culture and play important roles as autocrine embryotrophic factors.