Daniel J C, Kennedy J R
J Embryol Exp Morphol. 1978 Apr;44:31-43.
Crystalline inclusion bodies (CIB) may be found as prominent ultrastructural components of the trophoblast cells of rabbit blastocysts and of progestational uterine endometrium. In the work reported here we have sought to describe developmental steps in crystal formation, to correlate these events with embryonic age and to determine if the uterus is essential (either as a source or an environment) for crystal formation in the embryo. CIB, which are of a size and periodicity to make them appear to be clusters or packages of microtubules, are first detectable in embryos 4 days 6 h post coitum and by 41/2 days are well established in significant numbers. Another structural component, granular vesicles, may be seen in embryos as early as 21/2 days post coitum, and decrease in number during the same time the CIB are increasing. We believe that the CIB originate from the pre-existing granular vesicles and present electron micrograph evidence of crystal formation progressing from such vesicles. CIB formation does not occur in 41/2- to 5-day-old embryos which have been locked in the oviduct by a suture around the utero-tubal junction. However, when such tube-locked embryos are transplanted into the uterus, they develop crystals within 36 h thereafter. We conclude that the uterus is essential for CIB formation to occur in the rabbit embryo.
晶体包涵体（CIB）可能是兔胚泡滋养层细胞以及妊娠子宫子宫内膜突出的超微结构成分。在本文报道的研究中，我们试图描述晶体形成的发育步骤，将这些事件与胚胎年龄相关联，并确定子宫对于胚胎中晶体形成是否必不可少（无论是作为来源还是环境）。CIB的大小和周期性使其看起来像是微管的簇或束，最早在交配后4天6小时的胚胎中可检测到，到4.5天时大量形成。另一种结构成分，颗粒小泡，最早在交配后2.5天的胚胎中可见，并且在CIB数量增加的同一时间数量减少。我们认为CIB起源于先前存在的颗粒小泡，并提供了晶体从这些小泡开始形成的电子显微镜证据。在子宫输卵管交界处用缝线将4.5至5天大的胚胎固定在输卵管中，这些胚胎不会形成CIB。然而，当将这种被输卵管固定的胚胎移植到子宫中时，它们会在36小时内形成晶体。我们得出结论，子宫对于兔胚胎中CIB的形成至关重要。
