Enders A C, Meadows S, Stewart F, Allen W R
Department of Cell Biology and Human Anatomy, School of Medicine, University of California, Davis 95616-8643, USA.
J Anat. 1996 Jun;188 ( Pt 3)(Pt 3):575-89.
The mature preinvasive chorionic girdles of horse, mule, donkey and extraspecies donkey-in-horse conceptuses, and the very young endometrial cups on d 37 of gestation in mares carrying horse, mule and transferred donkey-in-horse conceptuses, were compared histologically and ultrastructurally to determine possible mechanisms underlying failure of endometrial cup development in the donkey-in-horse model of equine abortion. The progenitor chorionic girdle from the failing donkey-in-house pregnancy was similar in size to the normal donkey chorionic girdle but the trophoblast cells within the former were smaller, less organised and showed definite signs of degeneration and pyknosis. In the 37 d endometrial cups both in the horse and mule pregnancies, the recently invaded, differentiated and enlarging endometrial cup cells had penetrated deeply into the endometrial stroma and were becoming tightly packed between the persisting endometrial glands. In the donkey-in-horse pregnancy, on the other hand, relatively few donkey chorionic girdle cells had begun the invasion process and the majority of these, having penetrated and dislodged the horse luminal epithelium, did not penetrate the basement membrane beneath. Very few cells had reached the endometrial stroma and these had already attracted considerable numbers of lymphocytes to the area. It is concluded that unknown factors in the horse uterus affect adversely all phases of the development, attachment and invasion of donkey chorionic girdle cells, thereby leading to very little or no endometrial cup development and equine chorionic gonadotropin secretion in the extraspecific donkey-in-horse pregnancy created by embryo transfer.
对马、骡、驴以及种间马骡妊娠中成熟的侵袭前绒毛带，和妊娠37天时怀有马、骡胎儿以及移植马骡妊娠的母马子宫内非常早期的子宫内膜杯，进行了组织学和超微结构比较，以确定马流产的马骡模型中子宫内膜杯发育失败的潜在机制。来自失败的马骡妊娠的原始绒毛带大小与正常驴绒毛带相似，但前者的滋养层细胞较小，排列较松散，并有明确的退化和固缩迹象。在马和骡妊娠的37天子宫内膜杯中，最近侵入、分化并增大的子宫内膜杯细胞已深深侵入子宫内膜基质，并在持续存在的子宫内膜腺体之间紧密堆积。另一方面，在马骡妊娠中，相对较少的驴绒毛带细胞开始侵入过程，其中大多数在穿透并取代马腔上皮后，并未穿透其下方的基底膜。很少有细胞到达子宫内膜基质，并且这些细胞已经在该区域吸引了大量淋巴细胞。结论是，马子宫中的未知因素对驴绒毛带细胞发育、附着和侵入的所有阶段产生不利影响，从而导致在胚胎移植产生的种间马骡妊娠中，子宫内膜杯发育极少或根本不发育，且几乎没有马绒毛膜促性腺激素分泌。
