家兔囊胚在饲养层上的生长行为

GROWTH BEHAVIOR OF RABBIT BLASTOCYST ON FEEDER LAYER

研究了家兔囊胚在饲养层上的生长行为。结果表明，滋养层细胞铺展后，形成一层透明的膜状结构。覆盖在内细胞团之上。内细胞团在培养４８小时后，可见到一定程度的增殖，第３天增殖速度加快。生长的内细胞团可呈团状、条状、网状和混合型四种形态。混合型内细胞团分化出现较早，呈团状、条状和网状生长的内细胞团分化较晚。团状内细胞团一般在原位生长，而呈条状和网状生长的内细胞团增殖很快并迅速扩展到各处。滋养层细胞覆盖于未分化的内细胞团表面，剥离滋养层后，内细胞团迅速分化，说明滋养层具有保护兔胚内细胞团，减小外界环境对其诱发分化的作用。

This article reported the growth behavior of rabbit blastocysts on the feeder layer. After having spread,trophoblast formed a transparent and membranous structure covering inner cell masses(ICM). The obvious proliferation of ICM occured after cultured for 48 hours,and became faster form the 3rd day. ICM formed four kinds of colonies with different morphology,including the mass like, the net like,the streak like and the mixed colonies.The mixed colonies differentiated very early, while the others differentiated very late. Mass like ICM grew in a defined site,but streak like and net like ICM proliferated very fast and spread away very quickly. Undifferentiated ICM were covered with trophoblasts. When the trophoblasts were removed,ICM cells would differentiate rapidly. Trophoblasts seemed to play a role in protecting ICM from differentiation induced by environment.