SHR/SP与Wistar大鼠血管性痴呆模型的比较研究

摘要

Objective To evaluate the effect of permanent hypertension combined with hypoperfusion on the Stroke Prone spontaneously hypertensive rat (SHR/SP) vascular dementia model. Method Male SHR/SP and Wistar rats were randomly divided into SHR/SP sham operation group ,SHR/SP model group, Wistar sham operation group and Wistar model group respectively. All rats enrolled in the operation group were undergone a permanent ligation of bilateral carotid artery(2-VO). After the operation, 10 survival rats was available in each group. After 30 days, Morris maze tests were conducted for valuating the learning- memory abilities. Morphological changes of neuron cells and micro-blood vessels was observed. Result In place navigation training, the latency of Wistar sham operation group were less than that of rats in SHR/SP sham operation group, the latency of Wistar model group were less than that of rats in SHR/SP model group, the latency of SHR/SP model group were less than that of rats in Wistar model group (P＜0.05). In spatial probe ability test, the trails of rats in SHR/SP and Wistar sham operation groups were concentrated upon platform quadrant, while the those of SHR/SP and Wistar model groups were disorgnized. Neurons loss and micro-blood vessels stenosis of the rats in SHR/SP and Wistar model group groups were severer than that of the rats in SHR/SP and Wistar sham operation groups in the brain region. Conclusion The cognitive function of SHR/SP vascular dementia model was serious than Wistar rat vascular dementia model, both chronic permanent hypoperfusion and hypertension may lead to the loss of neurons and myelin which may result in memory dysfunction. Hypoperfusion is even more harmful than hypertension.%目的 探讨长期高血压与持续低灌流对自发性高血压脑卒中倾向大鼠(SHR/SP)血管性痴呆(VD)模型的影响.方法 选用雄性SHR/SP大鼠和Wistar大鼠,分为4组,分别为SHR/SP大鼠假手术组、模型组,Wistar大鼠假手术组、模型组,采用2VO(Bilateral carotid artery)分次结扎颈总动脉法制作VD模型,造模后选取存活大鼠,每组各10只.术后30 d采用Morrs水迷宫检测大鼠学习记忆能力并进行大脑病理切片观察.结果 在定位航行训练中,SHR/SP假手术组大鼠潜伏期明显长于Wistar假手术组大鼠,SHR/SP手术组大鼠潜伏期明显长于Wistar手术组大鼠,Wistar手术组大鼠潜伏期明显长于SHR/SP假手术组大鼠(P＜0.05).在空间探索实验中,Wistar假手术组、SHR/SP假手术组大鼠的游泳轨迹主要集中在平台象限,而Wistar模型组,SHR/SP模型组大鼠的游泳轨迹呈随机紊乱分布,跨越原平台次数明显少于两对照组大鼠.SHR/SP和Wistar大鼠手术组海马神经元损伤和小血管狭窄,与假手术组大鼠有明显区别.结论 SHR/SP大鼠VD模型,其大脑认知功能较Wistar大鼠VD模型受损更为严重,反应了持续高血压基础上产生的VD的特征,与持续高血压相比,持续低灌流对大脑认知功能的损害更加严重.