GALTON M
J Cell Biol. 1962 May;13(2):183-91. doi: 10.1083/jcb.13.2.183.
The DNA content of individual nuclei in four immature human placentas was determined by microspectrophotometric analysis of Feulgen-stained sections. The absence of mitosis in the syncytiotrophoblast, taken together with the finding of a diploid unimodal distribution, at a time of rapid placental growth, indicated that the syncytiotrophoblast possessed little or no intrinsic reproductive capacity. In contrast, the cytotrophoblast displayed considerable mitotic activity and was found to contain a high proportion of nuclei with DNA values in excess of the diploid amount, corresponding to DNA synthesis in interphase nuclei preparatory to division. From the complementary behavior of the two layers of trophoblast, with respect to evidence of reproductive ability, it is concluded that the rapid accumulation of nuclei in the syncytiotrophoblast, during the early development of the placenta, is accounted for by cell proliferation within the cytotrophoblast followed by alignment and coalescence of some daughter cells in the syncytiotrophoblast.
通过对福尔根染色切片进行显微分光光度分析，测定了四个未成熟人类胎盘单个细胞核的DNA含量。在胎盘快速生长阶段，合体滋养层中不存在有丝分裂，同时发现其二倍体单峰分布，这表明合体滋养层几乎没有或根本没有内在的繁殖能力。相比之下，细胞滋养层表现出相当活跃的有丝分裂活性，并且发现其中含有高比例的细胞核，其DNA值超过二倍体数量，这与分裂前间期细胞核中的DNA合成相对应。从滋养层两层在繁殖能力证据方面的互补行为可以得出结论，在胎盘早期发育过程中，合体滋养层中细胞核的快速积累是由细胞滋养层内的细胞增殖引起的，随后一些子细胞在合体滋养层中排列并融合。
