Abstract: AIM:To evaluate the effects of SDF-1α on neointimal hyperplasia of vein graft in rats. METHODS: Autologous vessels of external jugular were end-to-side grafted into carotid arteries of rats. Sixty Sprague Dawley rats weighing 250-300 g were randomly divided into two groups: model group and AMD3100 group. The vein grafts were harvested at 0, 3, 7, 14 and 28 days postoperatively and vessel wall thickness was measured. Immunofluorescence was used to detect the expression of SDF-1α on vein grafts. RESULTS: Results demonstrated that neointimal thickness of vein graft progressed gradually (P<0.01). The growth of vessel walls in the AMD3100 group decreased compared with that in the model group and protein expression of SDF-1α increased in vein grafts. Staining of SDF-1α emerged at 3 days after surgery and extended to 14 days. Protein expression of SDF-1α could still be detected at 28 days after grafting. CONCLUSION: SDF-1α plays an important role in the growth of vessel wall, and AMD3100 can reduce the thickness of vein graft.