Gordon J W, Dapunt U
Department of Obstetrics, Gynecology, and Reproductive Science, Mt. Sinai School of Medicine, New York, New York 10029.
Fertil Steril. 1993 Jun;59(6):1296-301. doi: 10.1016/s0015-0282(16)55993-7.
To develop an experimental model for embryos with a defect specific to hatching, with the purpose of clarifying the mammalian embryo hatching mechanism.
A microneedle was inserted under the zona pellucida (ZP) of mouse embryos, and either 1/2 or 1/4 of the blastomeres were mechanically destroyed. The remainder of embryos that developed into blastocysts were compared for hatching to controls wherein a microneedle was inserted and withdrawn without harming the embryo. Experiments were done to increase pressure within the perivitelline space to decrease the amount of ZP material to study the hatching mechanism.
University-based basic research laboratory.
When 1/2 or 1/4 of the embryo was destroyed and the remaining cells developed into healthy blastocysts within the intact zona, hatching was significantly impaired, and zona thickness was markedly increased relative to controls. When a mineral oil droplet was inserted under the zona to enhance a possible mechanical component of hatching, manipulated embryos were not restored to normal hatching, and hatching of unmanipulated blastocysts was not improved. However, when the zona was circumferentially thinned by application of acid Tyrode's solution, the hatching defect in manipulated "3/4 embryos" was corrected.
Because it is known that embryos with cells reduced by 1/2 or 1/4 have normal developmental potential, we conclude that the inability of such embryos to hatch from an intact zona constitutes a mouse model for a defect specific to hatching. Moreover, results from mineral oil droplet insertion and circumferential thinning of the zona indicate that normal hatching is accomplished predominantly, if not entirely, by zona lysis, not by pressure exerted against the zona by the expanding blastocyst.
建立一种针对孵化缺陷的胚胎实验模型，以阐明哺乳动物胚胎孵化机制。
将微针插入小鼠胚胎的透明带（ZP）下方，机械破坏1/2或1/4的卵裂球。将发育成囊胚的其余胚胎与仅插入并拔出微针而未损伤胚胎的对照胚胎进行孵化比较。通过增加卵周隙内的压力以减少ZP物质的量来研究孵化机制。
大学基础研究实验室。
当胚胎的1/2或1/4被破坏且剩余细胞在完整的透明带内发育成健康囊胚时，孵化明显受损，与对照相比透明带厚度显著增加。当在透明带下插入矿物油滴以增强可能的孵化机械因素时，操作过的胚胎未恢复正常孵化，未操作的囊胚孵化也未得到改善。然而，当用酸性台氏液使透明带周向变薄时，操作过的“3/4胚胎”的孵化缺陷得到纠正。
由于已知细胞减少1/2或1/4的胚胎具有正常发育潜能，我们得出结论，此类胚胎无法从完整透明带中孵化构成了一种针对孵化缺陷的小鼠模型。此外，矿物油滴插入和透明带周向变薄的结果表明，正常孵化主要（如果不是完全）通过透明带溶解完成，而不是由扩张的囊胚对透明带施加压力完成。
