Trophoblast functions, angiogenesis and remodeling of the maternal vasculature in the placenta.
One of the most important local adaptations to pregnancy is the change in maternal blood flow to the implantation site. In rodents and primates, new blood vessels form through angiogenesis, dilate and then become modified such that the blood enters into trophoblast cell-lined sinuses (hemochorial). Evidence from gene knockout mice suggests that factors from the placenta regulate the uterine vasculature. Consistent with this, trophoblast giant cells produce a number of angiogenic and vasoactive substances that may mediate these effects. Teratocarcinomas containing large numbers of trophoblast giant cells (derived from Parp1 gene-deficient ES cells) show similar 'hemochorial' host blood flow, implying that the effects are not specific to the uterine vascular bed. As in primates, murine trophoblast cells also invade into the uterine arteries of the mother. However, in normal pregnancy, dilation of the uterine arteries may be largely mediated by the effect of uterine natural killer cells.
Cross
J C
JC
Department of Biochemistry and Molecular Biology, Faculty of Medicine, University of Calgary, HSC Room 2279, 3330 Hospital Drive, N.W., Alta., T2N 4N1, Calgary, Canada. jcross@ucalgary.ca
Hemberger
M
M
Lu
Y
Y
Nozaki
T
T
Whiteley
K
K
Masutani
M
M
Adamson
S L
SL
D043925:Angiogenesis Inducing Agents / Q000502:physiology; D000818:Animals; D005260:Female; D006801:Humans; D018919:Neovascularization, Physiologic; D010920:Placenta / Q000098:blood supply* / Q000166:cytology; D021041:Placental Circulation / Q000502:physiology; D011247:Pregnancy; D014327:Trophoblasts / Q000166:cytology / Q000378:metabolism / Q000502:physiology*; D014599:Uterus / Q000098:blood supply
D043925:Angiogenesis Inducing Agents