Basic Research in Cardiology

, Volume 84, Issue 3, pp 259–267 | Cite as

Morphological and smooth muscle cell phenotypic changes in fetal rabbit aorta during early development

  • A. J. Cayatte
  • M. Ashraf
  • M. T. R. Subbiah
Original Contributions


Previous studies from our laboratory noted a) high aortic cholesterol esterification activity in the fetal rabbit, and b) increased susceptibility of fetal aortic explants to smooth muscle cell proliferation in culture, two features commonly associated with atherogenesis. This prompted us to examine in detail morphological development of fetal aorta and its relationship to fetal plasma cholesterol levels. Our studies made three important observations: 1) plasma cholesterol levels were high in early fetus which decreased at term; 2) in early fetus aortic endothelial cells appear to protrude into the lumen, whereas at birth the cells become flat, forming a continuous endothelium sheet; 3) in early fetus, smooth muscle cells exist predominantly in synthetic phenotype, while at birth the cells appear contractile. Despite the presence of synthetic smooth muscle cells and hypercholesterolemia in early fetal life, no accumulation of lipids was evident under transmission electron microscopy.

Key words

fetal rabbitaorta plasmacholesterol smooth muscle cell endothelium hypercholesterolemia transmission electron microscopy (TEM) 


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Copyright information

© Dr. Dietrich Steinkopff Verlag 1989

Authors and Affiliations

  • A. J. Cayatte
    • 1
  • M. Ashraf
    • 1
  • M. T. R. Subbiah
    • 1
  1. 1.Department of Internal Medicine and PathologyUniversity of Cincinnati Medical CenterCincinnatiUSA

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