Abstract: Objective To establish a steady and reliable rat model of carotid endarterectomy (CEA) by improved method, and to explore the changes of pathological morphology of vascular wall and proliferation of vascular smooth muscle cells after CEA. Methods Forty-eight SD rats were divided into two groups with 24 rats in each group (modified CEA group and conventional CEA group). The modified model was created by puncturing the carotid artery with a thin needle and detaining sutures before a longitudinal arteriotomy was performed; The success rate of modeling and the operation time were observed to evaluate the characteristics and reliability of two models. HE staining was performed to measure dynamic changes of the thickness of the vascular walls and immunohistochemistry was used to find expression of proliferating cell nuclear antigen (PCNA) on vessel wall on 3 days, 14 days and 28 days after operation. Result The model of rat carotid endarterectomy were successfully constructed. There was no significant difference in the success rate of modeling between two groups (87.5% vs 79.2%, P=0.46). The operation time (31.2±3.7 min) of modified group was significantly lower than that (40.9±4.2 min) of conventional group (P=0.00). Twenty-eight days after the operation, the thickness of the artery and the luminal diameter were significantly different from those of 3 days after the operation in modified group. The positive expression of PCNA was slightly higher on 3 days after operation, the highest on 14 days, and there was no positive expression on 28 days. Conclusion Modified rat carotid endarterectomy model has the characters of high success rate and simple handling, short operation time, and as a steady and reliable model, it is suitable for the study of restenosis after CEA.

Key words: Carotid endarterectomy(CEA), Animal models, Proliferating Cell Nuclear Antigen(PCNA)