Abstract: Objective · To establish New Zealand rabbit autogenous vein graft model and observe the changes of intimal hyperplasia in vein grafts at different time after grafting. Methods · 35 female New Zealand rabbits of 10 weeks old were randomly divided into 5 groups (7 rats in each group), i.e. postoperative 7 d group, postoperative 14 d group, postoperative 28 d group, postoperative 60 d group and normal control group. An animal model of external jugular vein common carotid artery bypass grafting was established, and the model construction steps were elaborated and optimized. Hematoxylin-eosin (H-E) staining was used to observe the intimal thickness after surgery and immunofluorescence staining was used to observe the of α-smooth muscle actin (α-SMA), which was one of the vascular smooth muscle cell (VSMC) differentiation marker protein. The effect of model construction was finally evaluated. Results · In addition to the normal control group, the other 28 New Zealand rabbits were successfully completed the vein graft operation. All the grafted veins kept unblocked except for one graft in postoperative 7 d group developed thrombosis, and the success rate was 96.4% (27/28). H-E staining and immunofluorescence staining showed significant intimal hyperplasia after vein grafting. Compared with the normal control group, the intimal thickness of the vein grafts was significantly increased (all P0.000) and the fluorescence intensity of α-SMA was significantly enhanced at each time group after surgery. Conclusion · New Zealand rabbit vein graft intimal hyperplasia modeling has an ideal success rate and good repeatability, which provides an ideal experimental model for studying the mechanism and prevention of restenosis after vein grafting.

Key words: autologous vein graft, intimal hyperplasia, animal model