一种适用于颅内外血管重建研究的大鼠慢性脑缺血模型

目的：检测结扎大鼠双侧颈内动脉及一侧椎动脉（3-VO）是否可以在保留颈外动脉的同时，造成大鼠慢性脑缺血。方法分别制造假手术对照组、双侧颈总动脉结扎组（2-VO）及3-VO组动物模型；于造模4周后行脑血流量测定；于第8周行Morris水迷宫实验测定大鼠的学习记忆能力；行为学实验结束后处死大鼠，观察大鼠海马CA1区细胞的形态学变化。结果脑血流测定结果显示与假手术（47±8．797）ml·min^－1·100 g^－1]相比，2-VO（24．30±8．999）ml·min^－1·100 g^－1]、3-VO（9．870±2．208）ml·min^－1·100 g^－1]组脑血流量值均降低，差异有统计学意义（P＜0．01）。 Morris水迷宫实验显示，2-VO组（14．78±7．84） s]、3-VO（14．86±7．96）s]组第5天潜伏期与假手术组（8．33±4．88）s]相比，时间较长，差异有统计学意义（P＜0．01），但2-VO组与3-VO组相比，其潜伏期无明显差异；与假手术组（37．20±9．21）s，（10．01±2．91）次]相比，2-VO组（20．13±5．80）s，（6．60±3．19）次]、3-VO组（20．05±5．76）s，（6．55±2．59）次]目标象限停留时间及穿越平台次数均显著减少，差异有统计学意义（P＜0．01）。2-VO、3-VO模型组海马CA1区有明显病理形态学改变。结论结扎双侧颈内动脉及一侧椎动脉可造成大鼠慢性脑缺血，并造成与2-VO相似的行为学表现。

A rat model of chronic cerebral hypoperfusion for the research of revascularization

Objective To estimate whether the ligation of bilateral internal carotid artery in combination with one vertebral artery can lead to chronic cerebral hypoperfusion. Methods The sham operation, 2-VO and 3-VO rat models were subjected to the matching operation. Four weeks after operation,the cortical blood flow was determined. The learning and memory abilities were measured with Morris water maze test eight weeks later,then the rats were sacrificed to observe the morphological change of hippocampal CA1 region. Results Compared with the sham operation group（（47±8.797）ml·min^-1·100 g^-1）,the cerebral blood flow of 2-VO（（24.30±8.999）ml ·min^-1·100 g^-1） and 3-VO（（9.870±2.208）ml·min^-1·100 g^-1） were significantly decreased （P〈0.01）. Compared with the sham operation group（（8.33±4.88）s）,escape latencies of Morris water maze of 2-VO group （（14.78±7.84）s） and 3-VO group（（14.86±7.96）s） in the fifth days also presented significantly increased （P〈0.01）,but rare difference between the two groups. Compared with the sham operation group （37.20±9.21） s, （10.01.±2.91）times],the target quadrant swimming time and crossing times of 2-VO group（（20.13±5.80）s, （6.60±3.19）times） and 3-VO group（（20.05±5.76）s,（6.55±2.59）times） in the fifth days also presented signifi-cantly decreased （P〈0.01）. There were distinct pathomorphology changes in hippocampal CA1 region of the two groups. Conclusion The ligation of bilateral internal carotid artery in combination with one vertebral artery can lead to chronic cerebral hypoperfusion,and can make the similar ethology representation with the 2-VO models.