Zybina E V
Tsitologiia. 1979 Dec;21(12):1419-26.
Intranuclear and cytoplasmic annulate lamellae in polyploid giant cells of the trophoblast have been studied in rat placenta on days 12--17 of development. The annulate lamellae are present in the cytoplasm within a limited time, being visible on day 12 only. These are arranged in bundles near the nucleus to be moving then to the cytoplasm. The end parts of annulate lamellae are broadened to make cisterns of rough endoplasmic reticulum. Unlike the cytoplasmic annulate lamellae, those found within the nucleus are seen in part of the nuclei investigated throughout the whole period examined to look as single structures (not gathered in bundles), they can be branching, separating closed spaces within the nucleus (making local swellings in the loci of branching; the latter having electron dense or transparent vesicles). Association with nuclear chromatin in some regions is a peculiar feature of the intranuclear annulate lamellae. This association is especially obvious at endoprophase in the cycle ofthe polytene nucleus during the somatic conjugation--chromonemes unite in a bundle and condense. Ultrastructural changes of the annulate lamellae is noted throughout the polytene nucleus cycle and during the cell differentiation. It is supposed that in the case of temporary labile chromosome polyteny in the nuclear cycle, which is characteristic of mammalian trophoblasts, annulate lamellae can well compare, in their function, with the synaptonemal complex--these prevent from too tight associations of homologues in the course of somatic conjugation of chromosomes.
对发育第12至17天大鼠胎盘滋养层多倍体巨细胞中的核内和胞质环孔板进行了研究。环孔板在胞质内存在的时间有限，仅在第12天可见。它们在细胞核附近成束排列，然后向细胞质移动。环孔板的末端部分变宽形成粗面内质网池。与胞质环孔板不同，核内环孔板在整个研究期间在所研究的部分细胞核中都可见，呈单个结构（不成束），它们可以分支，在核内分隔封闭空间（在分支部位形成局部肿胀；后者有电子致密或透明的小泡）。核内环孔板的一个特殊特征是在某些区域与核染色质相关联。在多线核周期的内前期，即在体细胞配对期间，这种关联尤为明显——染色线聚集在一起并浓缩。在整个多线核周期和细胞分化过程中都观察到了环孔板的超微结构变化。据推测，在核周期中暂时不稳定的染色体多线化情况下，这是哺乳动物滋养层的特征，环孔板在功能上可以很好地与联会复合体相比较——它们在染色体体细胞配对过程中防止同源物过度紧密结合。
