中文摘要：

目的：通过比较不同造模方法建立的血管性痴呆模型大鼠在学习记忆能力、术后死亡率、海马组织学检查等方面变化，探讨改良颈部小切口双侧颈总动脉永久性双重结扎血管性痴呆模型建立的可行性，为建立操作简单、死亡率低的血管性痴呆模型提供客观依据。 方法：将经水迷宫筛选的36只雄性SD大鼠随机分为假手术组、小切口双重永久性结扎模型组及分期永久性结扎模型对照组，每组各12只。小切口双重永久性结扎模型组在麻醉下一次性结扎后剪断大鼠双侧颈总动脉；分期永久性结扎模型对照组在麻醉下先分离结扎大鼠一侧颈总动脉，1周后再次在麻醉下行另一侧颈总动脉结扎；假手术组操作基本同模型组，但分离颈总动脉后不予以结扎。在术后48h及30d内记录各组大鼠死亡率，30d后对各组大鼠行水迷宫测试检测大鼠学习记忆能力，水迷宫测试结束后处死大鼠，观察大鼠脑海马组织的形态学变化。 结果：小切口双重永久性结扎模型组与分期永久性结扎模型对照组术后48h内死亡率比较无明显差异（P＞0.05），但前者大鼠死亡数量较后者少；术后30d内小切口双重永久性结扎模型组与对照组比较死亡率明显降低，差异有显著性意义（P＜0.05）；两种模型组大鼠与假手术组比较，学习记忆能力明显下降，差异有显著性意义（P＜0.05），而两种模型组大鼠学习记忆能力比较，差异无显著性意义（P＞0.05）；两种模型组大鼠大脑海马组织较假手术组大鼠均发生明显病理形态学改变。 结论：小切口双重永久性结扎方法可以较好地复制大鼠大脑永久性慢性灌注不足引起的血管性痴呆模型，引起与记忆相关的大鼠脑海马组织损害；小切口双重永久性结扎方法与分期永久性结扎方法在造模效果上没有本质的区别，但大鼠的死亡率却显著性降低。

英文摘要：

Objective： By comparing learning and memory ability, postoperative mortality and changes of hippocampus tissue for different vascular dementia model, we investigate the feasibility of modified bilateral carotid artery ligation dementia model with small incision, which constructs the objective basis for the establishment of vascular dementia model with simple operation and low mortality. Method： After being screened by the water maze, 36 male SD rats were randomly divided into sham group, small incision double permanent ligation group and staging permanent occlusion control group, with 12 cases in each group. Under anesthesia, we ligated and transected the bilateral carotid arteries in the small incision double permanent ligation group, while isolated and ligated carotid artery ligation for one side, and for the other side after one week in the staging permanent occlusion control group. The mortality was recored in 48h and 30d postoperatively. The learning and memory ability was assessed by water maze at 30d postoperatively. Finally, the rats were sacrificed to examine the hippocampal morphological changes. Result： Although the double permanent ligation group had the less number of dead rats, there was no obvious difference for the mortality between two model groups in 48h after operation. In 30d postoperatively, the mortality decreased significantly in the double permanent ligation group when compared with the control group （P〈0.05）. The ability of learning and memory had significant decrease for both model groups as compared with the sham group（P〈0.05）, while no significant difference between two model groups（P〉0.05）. Furthermore, the hippocampus also showed the obvious pathological changes in the model groups. Conclusion： Small incision double permanent ligation method can effectively reproduce the vascular dementia model caused by permanent chronic hypoperfusion. In spite of the same modeling results as the staging permanent ligation method, the small incision double permanent ligatio