Format

Send to

Choose Destination
See comment in PubMed Commons below
Am J Anat. 1989 Sep;186(1):85-98.

Trophoblast differentiation during the transition from trophoblastic plate to lacunar stage of implantation in the rhesus monkey and human.

Author information

1
Department of Human Anatomy, School of Medicine, University of California, Davis 95616.

Abstract

The transition from the trophoblastic plate stage to the early lacunar stage was examined in a series of implantation sites from the rhesus monkey, timed on the basis of the preovulatory estrogen peak, and prepared for transmission electron microscopy. This transition was compared with specimens from stage 5a, b, and c in the Carnegie collection of human embryos. The transition was marked by the differentiation of a new type of syncytial trophoblast--namely, a unilaminar microvillous polarized syncytium, which developed throughout the trophoblastic plate, forming characteristic intrasyncytial clefts. The rapid development of this type of syncytium created a nonclotting chamber for maternal blood wherever trophoblast intrusion into maternal vessels created confluence. Although the nature of the material in the Carnegie series precluded cytological characterization of the trophoblast, there is evidence that a similar transition occurs in human trophoblast and that in the human also the appearance of lacunae marks a change from an early invasive trophoblast to a situation in which growth is more significant.

PMID:
2782290
DOI:
10.1002/aja.1001860107
[Indexed for MEDLINE]
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Loading ...
    Support Center