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.
Article| May 01 1962
DNA CONTENT OF PLACENTAL NUCLEI
From the Department of Obstetrics, Harvard Medical School, Boston.
Dr. Galton's present address is Department of Pathology, Dartmouth Medical School, Hanover, New Hampshire
Received: July 16 1961
Online ISSN: 1540-8140
Print ISSN: 0021-9525
Copyright © 1962 by The Rockefeller Institute Press
Michael Galton; DNA CONTENT OF PLACENTAL NUCLEI . J Cell Biol 1 May 1962; 13 (2): 183–191. doi: https://doi.org/10.1083/jcb.13.2.183
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