Miceli D C
Adv Exp Med Biol. 1986;207:167-83. doi: 10.1007/978-1-4613-2255-9_11.
In this communication I have attempted to present an overview of some contributions to the understanding of the oviduct-egg interaction in amphibians. According to data from other authors, the vitelline envelope of the newly ovulated egg constitutes a barrier for the passage of spermatozoa. Our results demonstrated that only after they have been affected by substances released by the first 1-3 cm of the oviduct (pars recta), is the envelope sensitive to spermlysins and the oocytes fertilizable. This functional change is matched by biological, physicochemical and morphological differences in the vitelline envelope. The fact that the pars recta activity is affected by the sexual cycle and that in ovariectomized females - devoid of active pars recta - the biological activity can be restored by steroid hormones, strongly suggests that the molecules involved in fertilization are synthesized and secreted during specific steps of the reproductive cycle. The pars recta-oocyte interaction probably involves more than one type of molecules, considering the observations made on the carbohydrate metabolism of coelomic eggs, which could be altered by the oviducal secretions. Several explanations for the pars recta mechanism of action have been suggested. One is a direct action on the sperm; pars recta molecules - engulfed in the vitelline envelope - would trigger the acrosome reaction. We propose the unmasking of specific vitelline envelope sites for sperm interaction. Material on the outer surface of the VE can be removed or altered by the enzymatic activity - similar to plasmin and trypsin - detected in the pars recta secretions.
在本通讯中，我试图概述一些有助于理解两栖动物输卵管与卵子相互作用的研究成果。根据其他作者的数据，新排出卵子的卵黄膜对精子的通过构成了障碍。我们的研究结果表明，只有在受到输卵管前1 - 3厘米（直肠部）释放的物质影响后，卵黄膜才对精子溶解素敏感，卵母细胞才能受精。这种功能变化与卵黄膜在生物学、物理化学和形态学上的差异相匹配。直肠部的活性受性周期影响，而在切除卵巢的雌性动物中（缺乏活跃的直肠部），类固醇激素可恢复其生物学活性，这有力地表明参与受精的分子是在生殖周期的特定阶段合成和分泌的。考虑到对体腔卵碳水化合物代谢的观察结果，输卵管分泌物可能会改变这种代谢，直肠部与卵母细胞的相互作用可能涉及多种类型的分子。关于直肠部作用机制有几种解释。一种是对精子的直接作用；包裹在卵黄膜中的直肠部分子会引发顶体反应。我们提出，卵黄膜上特定的精子相互作用位点被暴露出来。卵黄膜外表面的物质可被直肠部分泌物中检测到的类似纤溶酶和胰蛋白酶的酶活性去除或改变。
