全脑缺血再灌注对大鼠空间学习记忆的影响

Investigation of the effects of global ischemia and reperfusion on learning and memory in rats

目的:探讨缺血性脑损伤对大鼠空间分辨学习和记忆能力的影响。方法:17只Wistar雄性大鼠随机分成两组,缺血组采用改良的Pulsinelli四血管闭塞法(4VO)建立大鼠全脑缺血模型,假手术组则只手术不缺血。缺血第8天开始利用Morris水迷宫测试来检测其空间分辨学习和记忆的能力。然后进行灌注固定,经石蜡切片和尼氏染色,最后在显微镜下观察海马CA1区神经元的存活情况,从而确定全脑缺血模型制作的成功与否。结果:缺血性脑损伤组大鼠CA1区约90%神经元死亡,未死亡的神经元散在分布,其形态与正常神经元形态稍异,而假手术组海马CA1区神经元排列整齐,并未发生死亡,说明模型制作成功;在Morris水迷宫测试前4天的训练中,缺血性脑损伤组大鼠平均找到平台时间明显多于假手术组大鼠所用时间,经统计分析两组间有显著性差异(P<0.05),而两组间的游泳速度未见显著性差异(P>0.05);第5天撤掉平台后,缺血性脑损伤组大鼠在原平台所在象限所走的路程占总路程的比例也明显比假手术组少(P<0.05)。说明与假手术组相比,缺血性脑损伤组大鼠的空间分辨学习与记忆能力明显降低。结论:缺血性脑损伤使大鼠的学习、记忆功能受到损害。

Objective： To study the rat＇s learning and memory capability after global brain ischemia.Method： Seventeen male wistar rats were divided into two groups： ischemic group and sham group,use four vascular occlusion（4-VO）, make global brain ischemic（GBI）.The ischemic group was to burn shut the two sides＇ vertebral artery（VA） then after twenty four hours occlusion the left and right common carotid artery,sham group did nothing.After one week test water maze,then dabblepexy and make the cerebrum into paraffin section,count the hippocampus＇CA1 zoon still live neuron. Result： 90% neuron died in CA1 zoon in the ischemic group,the still live neuron stay in disorder,and their shape has changed.But the neuron in sham group didn＇t change.The result showed that the model building succeeded.The average time to find the plate of the rat use in ischemic group is longer then that of sham group＇s,which showed that the learning and memory capability of ischemic group＇s rat is lower.Conclusion： The rat＇s learning and memory capability in ischemic group is significantly lower.