Mesenchymal stem cells Involved in vascularization,and improve heart function in rat acute myocardial infarction model.

Objective To investigate improvement of heart function through rat marrow mesenchymal stem cells(MSCs) involved in Vascularization in acute myocardial infarction(AMI).Methods MSCs were isolated from adult in bred Wistar rats,cultured and expanded in vitro,and labeled with DAPI.The animal model of AMI was established by the left anterodecendant arteries (LAD)occlusion(60min) with reperfusion in rat s of the same species.One week after operation,1.0×107MSCs were injected into infarcted areas.Four week after transplantation,cardiac function was analyzed.And heart tissues were taken after the measurement of hemodynamics.Histology and morphometric measurement was observed by image Analysis system in microscope and MSCs expressions of CD31 and SM-Actin detected by immunofluorescent cytochemistry.Results The transplanted MSCs in AMI area had significantly higher expression rates of CD31 and SM-Actin 4 weeks after transplantation.There were a decreased infarct size,greater vascular density,thicker left ventricle wall in MSCs-treated group.Conclusion In a rat AMI model,MSCs differentiated into smooth muscle cells and endothelial cells,resulting in vascularity and improved cardiac function.