【摘要】 用免疫手术去除小鼠早期胚胎的外层细胞或滋养层细胞后，其内细胞团（ＩＣＭ）经２４ｈ体外培养后能够重新形成滋养层，从晚期桑椹胚、早期胚泡和晚期胚泡分离的ＩＣＭ的滋养层分化率分别为７０．３％、６９．３％和１１．１％，晚期胚泡ＩＣＭ的滋养层分化率明显低于早期胚泡和桑椹胚的滋养层分化率。实验结果表明小鼠早期胚泡的ＩＣＭ仍然具有较强的分化为滋养层的能力，但晚期胚泡的ＩＣＭ分化为滋养层的能力明显减弱．从而推断晚期胚泡的ＩＣＭ在分化方向上发生了重要的内在变化。更多还原

【Abstract】 fter outside cells or trophoblasts were removed from mouse early embryos by immunosurgi-cal method, the inner cell mass’(ICMs)can regenerate trophoblasts after they were cultured for24 h.in vitro. The differentiation rates of trophobiast from ICMs isolated from late morula ,earlyblastocysts,and late blastocysts were 70. 93%, 69.3%and 11.1%,respectively. The differentia-tion rate of trophoblast from late blastocyst was much lower than that from early blastocysts andmorula. The result of this experiment indicated that the early blastocyst ICM retains the potentialto form trophoblast , but the late blastocyst ICM losts this kind of ability gradualy. It suggestedthat the important internal change had taken place in the late balstocyst ICM cells in the directionof differentiation.更多还原