Talansky B E, Gordon J W
Department of Physiology and Biophysics, Mount Sinai School of Medicine, New York 10029.
Gamete Res. 1988 Nov;21(3):277-87. doi: 10.1002/mrd.1120210309.
The effects of zona drilling on mouse embryo development in vitro were evaluated. Following insemination, sperm were immediately concentrated at the area of drilling, and in zona-drilled eggs, pronuclei appeared 30-50 min earlier than in zona-intact controls. Zona-drilled oocytes fertilized at significantly higher rates than undrilled controls and, consequently, a greater percentage of eggs inseminated after zona drilling reached the blastocyst stage. The attrition rates of zona-drilled embryos at each cleavage stage did not differ significantly from controls. Manipulated embryos exhibited unique cleavage patterns. Some embryos lost their zonae entirely, whereas others became partially extruded at early cleavage stages. These anomalies led to separation of blastomeres from the zygote proper, aggregation of embryos to form giant composite morulae and blastocysts, and occasionally to formation of miniature twin blastocysts. These characteristics of cleavage indicate that although zona drilling of a cohort of oocytes is likely to lead to an increased number of live births relative to controls, some developmental abnormalities can be encountered, and these may be associated with embryo loss, spontaneous chimerism, or possibly with conception of monozygotic twins.
评估了透明带打孔对小鼠胚胎体外发育的影响。授精后，精子立即聚集在打孔区域，并且在打孔的卵子中，原核出现的时间比未打孔的对照组早30 - 50分钟。打孔的卵母细胞受精率显著高于未打孔的对照组，因此，打孔后授精的卵子中有更大比例发育到囊胚阶段。打孔胚胎在每个分裂阶段的损耗率与对照组无显著差异。操作后的胚胎表现出独特的分裂模式。一些胚胎完全失去了透明带，而另一些在早期分裂阶段部分挤出。这些异常导致了卵裂球与正常合子分离、胚胎聚集形成巨大的复合桑葚胚和囊胚，偶尔还会形成微型双囊胚。这些分裂特征表明，虽然相对于对照组，对一批卵母细胞进行透明带打孔可能会导致活产数量增加，但可能会出现一些发育异常，这些异常可能与胚胎丢失、自发嵌合体形成或可能与单卵双胞胎的受孕有关。
