This Article Full Text (PDF) References Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Add to Saved Citations Download to citation manager Request Permissions Request Reprints Add to My Marked Citations Citing Articles Citing Articles via Google Scholar Citing Articles via Scopus Google Scholar Articles by Cheung, C. Y. Articles by Brace, R. A. Search for Related Content PubMed PubMed Citation Articles by Cheung, C. Y. Articles by Bogic, L. Articles by Gagnon, R. Articles by Harding, R. Articles by Brace, R. A. Social Bookmarking                         What's this?

Morphologic Alterations in Ovine Placenta and Fetal Liver Following Induced Severe Placental Insufficiency

Division of Perinatal Medicine, Department of Reproductive Medicine, University of California at San Diego, La Jolla, California; Department of Obstetrics and Gynecology and of Physiology, University of Western Ontario, London, Ontario, Canada; and Department of Physiology Monash University, Clayton, Victoria, Australia; cycheung{at}ucsd.edu

Ljubica Bogic, PhD

Robert Gagnon, MD

Richard Harding, DSc

Robert A. Brace, PhD

Division of Perinatal Medicine, Department of Reproductive Medicine, University of California at San Diego, La Jolla, California; Department of Obstetrics and Gynecology and of Physiology, University of Western Ontario, London, Ontario, Canada; and Department of Physiology Monash University, Clayton, Victoria, Australia

Objectives: Umbilical-placental embolization with microspheres has been used as a model of placental insufficiency and intrauterine growth restriction (IUGR). However, the effects of embolization on placental structure and organ morphology of the resulting IUGR fetus are relatively unexplored. In this study using ovine fetuses, we determined the location and distribution of microspheres within the placenta and explored the extent of placental and fetal organ morphologic changes induced by placental embolization. We hypothesized that microspheres administered into the umbilical circulation over 4 days would cause placental damage without significant morphologic alterations in fetal kidney or liver.

Methods: Eleven pregnant sheep at 118 ± 1 (SE) days' gestation were studied. In six fetuses, embolization was induced by injection of 15-µm diameter microspheres on 4 successive days into the fetal descending aorta proximal to the umbilical arteries. Five fetuses served as time controls.

Results: In embolized fetuses, microspheres were detected in the placenta embedded in the fetal cytotrophoblastic layer on maternal parenchyma adjacent to villous cytotrophoblasts. Fetal cytotrophoblasts appeared normal except for loss of distinct separation between fetal and maternal cell layers. Microspheres were also detected in the fetal membranes within capillaries. The body weights of embolized fetuses were lower than controls, as were the body weight-normalized liver but not kidney weights. In the liver of the embolized fetuses, the number of hematopoietic cell clusters was markedly reduced, whereas the fetal kidneys appeared normal.

Conclusions: We conclude that after 5 days of umbilical-placental embolization, microspheres were concentrated at the fetal villi proximal to the apical maternal-fetal interface and in the membranes. There were noticeable morphologic changes in the embolized placentas, with no apparent gross damage to the placenta. The reduction in fetal liver weight and liver extramedullary hematopoietic cell abundance associated with embolization may predispose the fetus to alterations in liver function that could persist after birth.

Key Words: Placental insufficiency • microspheres • sheep • fetal membranes • kidney

Journal of the Society for Gynecologic Investigation, Vol. 11, No. 8, 521-528 (2004)
DOI: 10.1016/j.jsgi.2004.06.010


CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    Twitter    What's this?