Objective:To investigate the effect and its possible mechanism of peripheral blood mesenchymal stem cells(MSCs)on endothelium repair in Rabbits with balloon-induced injury carotid.Methods:Purified MSCs were Obtained from peripheral blood through combining density gradient centrifugation with repeating adherence cultivation after the application of Granulocyte colony-stimulating factor(G-CSF)for 5 days in rabbits with atherosclerosis stenosis carotid artery

and marked with enhanced green fluorescent protein(EGFP).EGFP marked MSCs were transplanted into the rabbits in the transplantation of MSCs groups and equivalence culture solution was injected in the control groups through surrounding ears veins after balloon-induced carotid artery in rabbits.The specimens of carotid artery were harvested to use for the analysis of vessels morphology and endothelialization in 7

14

28 days of post-operative

and the homing MSCs were identified.Results:Carotid artery morphology analysis in each stage indicates that intima hyperplasia is obviously less in the transplantation of MSCs groups than that in the control groups(P<0.01).Endothelialization analysis shows that the degree of endothelialization is better in the transplantation of MSCs groups than that in the control groups(P<0.01).EGFP-positive cells and EGFP-and CD31-positive cells were found in the carotid artery of each stage in the transplantation of MSCs groups

but there was nothing in the control groups.Conclusion:Intravenous transplantation of PBMSCs may accelerate reendothelialization and attenuate neointimal thickening in rabbits with balloon-induced injury carotid.