ObjectiveTo study the cell apoptosis and the dynamic expression and significance of apoptosis-related genes in graft veins. MethodsA rat experimental model of autogenous graft vein was established by transplanting the right external jugular vein to infrarenal abdominal aorta in 100 Wistar rats. TUNEL and immunohistochemistry were used to detect the apoptosis, the expression of apoptosis-related genes bcl-2 and bax in vascular smooth muscle cells (VSMCs) of graft veins. ResultsWithin the 8 weeks after transplantation, the apoptotic VSMCs in the graft veins were much more than those in the control group with the apoptotic rate reaching the peak〔(28.5±16.6)%〕 on the 2nd week and dropping to (8.1±2.8)% during the 4th to 8th week. There was statistical difference compared to the control group 〔(0.5±0.2)%, P<0.01〕. From 1 to 2 weeks, the positive rate of bcl-2 was (22.1±5.4)% which was higher than that of the control group and the 4-8 week group (P<0.01); from 1 to 6 weeks, the expression of bax was higher than that of the control group 〔(5.5±2.3)%〕 and the postoperative 8th week group 〔(8.2±2.9)%, P<0.01〕.Conclusionbcl-2 and bax protein may be involved in the regulation of apoptosis of VSMCs. Apoptosis of VSMCs may be an important factor in graft remodeling and graft vein stenosis.