title: Vascular endothelial growth factor in monochorionic twins with twin-twin transfusion syndrome.
abstract: OBJECTIVE
  The purpose of this study was to determine vascular endothelial growth factor (VEGF) concentrations in the donor and the recipient in monochorionic twin pregnancies with twin-twin transfusion syndrome (TTTS) and single pregnancies in order to investigate the involvement of VEGF in the pathophysiology of TTTS.
  
  
  METHODS
  Six twin pregnancies in 11 monochorionic twin pregnancies complicated with TTTS and 11 single control pregnancies were compared. Gestational age-matched fetal blood and placental samples were obtained at birth. Serum VEGF concentration in the umbilical vein was measured by an enzyme-linked immunoabsorbant assay. Tissue protein expression of VEGF was determined by using immunohistochemistry. Western blot analysis and scanning densitometry were used to quantify and compare the VEGF expression in the terminal villi.
  
  
  RESULTS
  Serum VEGF concentrations in the umbilical vein in both donors and recipients tended to be higher than those in the controls. Immunolocalization of VEGF in terminal villous placenta samples in both donors and recipients was mainly observed in the syncytiotrophoblastic layer and vascular endothelial cells with less intense staining in stromal cells. The expression of VEGF in the donor placenta increased significantly (p=0.006) compared to that in the control placenta, but the expression of VEGF in the recipients tended to be higher than in the controls.
  
  
  CONCLUSIONS
  Intrauterine circulatory imbalance may induce changes in VEGF expression and these alterations may be involved in both donor and recipient in the pathogenesis of TTTS, due to the maintenance of hemodynamic stability between the circulation of the twins.
authors.affiliation: Department of Obstetrics and Gynecology, University of Tokushima, School of Medicine, Tokushima, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Morine
authors.forename: T
authors.initials: T
authors.lastname: Nobunaga
authors.forename: T
authors.initials: T
authors.lastname: Mizutani
authors.forename: K
authors.initials: K
authors.lastname: Yamanaka
authors.forename: K
authors.initials: K
authors.lastname: Wasada
authors.forename: K
authors.initials: K
authors.lastname: Maeda
authors.forename: N
authors.initials: N
authors.lastname: Suehara
authors.forename: T
authors.initials: T
authors.lastname: Yasui
authors.forename: M
authors.initials: M
authors.lastname: Irahara
mesh_terms: D005260:Female; D005330:Fetofetal Transfusion / Q000150:complications / Q000503:physiopathology*; D006801:Humans; D007231:Infant, Newborn; D010920:Placenta / Q000378:metabolism; D011247:Pregnancy; D014430:Twins, Monozygotic / Q000097:blood*; D042461:Vascular Endothelial Growth Factor A / Q000097:blood* / Q000235:genetics
chemical_list: C467484:VEGFA protein, human; D042461:Vascular Endothelial Growth Factor A