Welsh A O
Department of Cell Biology and Human Anatomy, University of California, Davis 95616.
Microsc Res Tech. 1993 Jun 15;25(3):223-45. doi: 10.1002/jemt.1070250305.
During blastocyst implantation and placentation in common laboratory rodents, trophoblast cells come into increasingly more intimate associations with the endometrium and, eventually, are in contact with maternal blood. Uterine cell death is one mechanism for removing uterine tissues, primarily epithelial cells, and decidual cells that intervene between trophoblast cells and maternal blood. Mechanisms of cell death and the signals that initiate and regulate it are not well understood. According to current theories, cell death is either gene-directed or the result of traumatic injury, and classification of cell death is based on ultrastructural and biochemical criteria that hypothetically reflect underlying molecular mechanisms. Although the term apoptosis is extensively used to describe all aspects of gene-directed cell death and the term necrosis to describe traumatic death, ultrastructural studies indicate that there are morphological variations of the established criteria, and these could reflect variations of underlying mechanisms. Recent light and electron microscopic work has shown that timing and ultrastructure of uterine cell death at the gestation site varies with region suggesting that initiation and control of cell death is complicated and that more than one mechanism of cell death may be operative. Current information indicates that uterine cell death is most likely part of an intrinsic response of the endometrium to the conceptus, and other than acting as a stimulus to elicit the uterine response, the conceptus probably plays only a minor role in regulating the death of endometrial cells in these species.
在常见实验啮齿动物的囊胚着床和胎盘形成过程中，滋养层细胞与子宫内膜的联系日益紧密，最终与母体血液接触。子宫细胞死亡是清除子宫组织（主要是上皮细胞和蜕膜细胞）的一种机制，这些细胞介于滋养层细胞和母体血液之间。细胞死亡的机制以及启动和调节该过程的信号目前尚不清楚。根据当前理论，细胞死亡要么是基因导向的，要么是创伤性损伤的结果，细胞死亡的分类基于超微结构和生化标准，这些标准假设反映了潜在的分子机制。尽管“凋亡”一词被广泛用于描述基因导向细胞死亡的各个方面，“坏死”一词用于描述创伤性死亡，但超微结构研究表明，既定标准存在形态学差异，这些差异可能反映了潜在机制的变化。最近的光学和电子显微镜研究表明，妊娠部位子宫细胞死亡的时间和超微结构因区域而异，这表明细胞死亡的启动和控制很复杂，可能存在多种细胞死亡机制。目前的信息表明，子宫细胞死亡很可能是子宫内膜对胚胎的一种内在反应的一部分，除了作为引发子宫反应的刺激因素外，胚胎在这些物种中调节子宫内膜细胞死亡方面可能只起次要作用。
