title: Validation of the vitronectin knockout mouse as a model for studying myocardial infarction: Vitronectin appears to influence left ventricular remodelling following myocardial infarction.
abstract: BACKGROUND
  Vitronectin (VN) is an abundant acute-phase plasma protein that regulates cell adhesion and migration as well as interactions with components of the plasminogen activator/plasmin system, specifically plasminogen activator inhibitor type 1. This system plays a major role in tissue remodelling regulating wound healing after myocardial infarction.
  
  
  OBJECTIVE
  To investigate the feasibility of using VN knockout mice (VN(-/-)) to study the role of VN on ventricular remodelling following myocardial infarction.
  
  
  METHODS
  Specifically bred VN(-/-) mice and normal wild-type (VN(+/+)) mice underwent coronary artery ligation and were assessed 28 days postligation using echocardiography and morphometric histology.
  
  
  RESULTS
  No difference was observed between VN(-/-) mice and VN(+/+) mice with respect to gross phenotype, weight, coronary anatomy or echocardiographically measured ejection fraction (56%). Following myocardial infarction, VN(-/-) mice exhibited less ventricular dilation and less impairment in echocardiographic ejection fraction compared with VN(+/+) mice (48% versus 41%; P=0.01). VN(-/-) mice also exhibited smaller infarcts on morphometric analysis.
  
  
  CONCLUSIONS
  The results of the present study confirmed the feasibility of using coronary artery ligation in VN knockout mice to investigate the role of VN in post-myocardial infarction remodelling. The absence of VN appears to result in favourable effects on wound healing. These data suggest that this model may offer novel insights into the role of VN in the regulation of myocardial remodelling.
authors.affiliation: Department of Pathology and Laboratory Medicine, University of British Columbia and the James Hogg iCAPTURE Centre for Cardiovascular and Pulmonary Research, St Paul's Hospital, Vancouver, British Columbia.
authors.forename: Gordon E
authors.initials: GE
authors.lastname: Pate
authors.forename: Hubert P
authors.initials: HP
authors.lastname: Walinski
authors.forename: Lubos
authors.initials: L
authors.lastname: Bohunek
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Podor
keywords: Myocardial infarction; Remodelling; Vitronectin