title: Delayed vasculogenesis and impaired angiogenesis due to altered Ang-2 and VE-cadherin levels in the chick embryo model following exposure to cadmium.
abstract: OBJECTIVE
  Cadmium (Cd) causes chick embryo malformation and abnormal extra-embryonic vasculature. This study investigates the effect of Cd on vasculogenesis, quantifies extra-embryonic vascular development following exposure to cadmium acetate (CdAc).
  
  
  METHODS
  After 48 or 60 h incubation, chicks were explanted and treated with 50 µl of 50 µM CdAc or equimolar sodium acetate. Embryos were again incubated then re-examined 4, 8, 24 and 48 h later. Gross morphological and histological manifestations were noted. Vasculogenesis was assessed by the development of omphalomesenteric vessels from blood islands. Sinus terminalis (ST), area vasculosa (AV), vessel density and embryo crown-rump length (CRL) were measured. Ang-2 and VE-cadherin mRNA expression was analysed by RT-PCR.
  
  
  RESULTS
  Vasculogenesis was delayed on gross and histological examination. ST length, AV area, vessel density and CRL were significantly reduced in the Cd group. Ang-2 was increased 4 h after exposure to Cd, whereas VE-cadherin was reduced.
  
  
  CONCLUSIONS
  Cd exposure inhibits normal development of extra-embryonic vasculature in line with growth retardation of the chick embryo in association with altered expression of Ang-2 and VE-cadherin.
authors.affiliation: School of Medicine and Medical Science, University College Dublin, Belfield, Dublin 4, Ireland. anna.gheorghescu@yahoo.com.
authors.forename: A
authors.initials: A
authors.lastname: Gheorghescu
authors.affiliation: School of Medicine and Medical Science, University College Dublin, Belfield, Dublin 4, Ireland.
authors.forename: J
authors.initials: J
authors.lastname: Thompson
mesh_terms: D000085:Acetates / Q000494:pharmacology*; D042702:Angiopoietin-2 / Q000378:metabolism*; D000818:Animals; D015703:Antigens, CD / Q000187:drug effects / Q000378:metabolism*; D015820:Cadherins / Q000187:drug effects / Q000378:metabolism*; D002104:Cadmium / Q000494:pharmacology*; D002454:Cell Differentiation / Q000187:drug effects / Q000502:physiology; D002642:Chick Embryo; D047108:Embryonic Development / Q000187:drug effects* / Q000502:physiology; D009024:Morphogenesis / Q000187:drug effects* / Q000502:physiology; D018919:Neovascularization, Physiologic / Q000187:drug effects* / Q000502:physiology; D060888:Real-Time Polymerase Chain Reaction; D000099152:Cadherin 5
chemical_list: D000085:Acetates; D042702:Angiopoietin-2; D015703:Antigens, CD; D015820:Cadherins; D002104:Cadmium; D000099152:Cadherin 5; C028031:cadmium acetate
keywords: Angiopoietin; Area vasculosa; Cadmium; Chick embryo; Extra-embryonic vasculature; Haemangioblast; Sinus terminalis; VE-cadherin; Vessel density