尼莫通对缺氧缺血性脑损伤新生大鼠学习和记忆的影响  

Influence of Nimotop on Long-Term Learning and Memory of Neonatal Rats with Hypoxia-Ischemia Brain Damage

作　　者：王作军[1] 谢集建[1] 李涛[1] 吕义荣[1] 潘军[1] 陈宝芳[1] 

机构地区：[1]十堰市太和医院郧阳医学院附属医院儿童医疗中心,湖北十堰442000

出　　处：《实用儿科临床杂志》2007年第14期1061-1063,共3页Journal of Applied Clinical Pediatrics

摘　　要：目的观察缺氧缺血性脑损伤(HIBD)对新生大鼠远期学习和记忆的影响及尼莫通治疗效果,探讨HIBD影响学习记忆的机制。方法选择7d龄Wistar大鼠49只。其中34只通过接扎左侧颈总动脉、吸入氧体积分数为(80±5)mL/L的氮氧混合气体2h,制作新生大鼠HIBD模型。制模后的大鼠随机分为HIBD组(21只)、尼莫通治疗组(13只)。余大鼠为正常对照组(15只)。尼莫通用量为160μg/kg,腹腔注射,1次/d,共5d。至生后80d左右进行Y-迷宫分辨学习和记忆能力测试,透射电镜观察各组大鼠海马CA1区锥体神经元的超微结构变化。结果HIBD组大鼠在Y-迷宫中达到学会标准前所需的训练次数为(32.82±8.22)次,明显多于正常对照组(20.67±7.03)次(P<0.01),而24h后的记忆保持率[(59.0±21.32)%]显著低于正常对照组[(80.0±18.9)%](P<0.05)。尼莫通治疗组大鼠的学习能力较HIBD组明显提高(20.69±7.96P<0.01),记忆能力[(69.13±22.42)%]亦有所改善,但差异不显著(P>0.05)。HIBD组CA1锥体神经元较正常对照组明显破坏,可见部分核膜消失,线粒体嵴模糊、数量明显减少及内质网扩张等改变,而尼莫通治疗组细胞器破坏减轻,核膜较完整,线粒体嵴可见。结论尼莫通可明显提高大鼠HIBD后的学习能力,对记忆亦有改善,脑缺氧缺血所引起海马组织超微结构的改变是HIBD所致学习记忆脑功能障碍的重要神经机制。Objective To investigate the mechanisms and influence of nimotop on long - term learning and memory in neonatal rats after hypoxia - isehemia. Methods Thirty - four seven - day - old postnatal Wistar rats were subjected to left common carotid artery ligation followed by exposure to （ 80 ± 5 ） mL/L oxygen at 37℃ for 2 h. The animals were randomly divided into two groups. Thirteen rats pups were injected intraperitoneally with 160 μg/kg nimotop immediately following cerebral hypoxia -isehemia, once a day,5 days for a treatment course. Control animals were injected with an equivalent volume of normal saline （ n = 21 ）. Fifteen healthy rats were as control group. When the rats were abouf 80 - day - old, their discrimination learning and memory keeping percentage were measured by test of Y - maze. The uhrastrueture of the neurons of hip- poeampal CA1 subregion were studied by eleetronmieroseope. Results The Y - maze discrimination learning abilities （ P 〈 0.01 ） and memory keeping percentage （ P 〈 0.05 ） decreased significantly in hypoxie - isehemie animals. Y - maze discrimination learning abilities increased significantly in the HI rats of nimotop group （ P 〈 0.01 ） , but had no effect on memory keeping. Compared with control group, the nucleus membrane and mitoehondria of hippoeampal CA1 neurons in the HI rats were distorted,while the uhrastrueture in nimotop group was remarkably relieved. Conclusions HIBD leads rats to disorders of learning and memorizing abilities which may be correlated with the changes of hippocampal CA1 neu- rons. Nimotop may be of value to improve the ability of Y- maze discrimination learning, but it has no obvious beneficial effect on memory keeping.

关 键 词：缺氧缺血 脑 尼莫通 学习记忆 大鼠 

分 类 号：R722.1[医药卫生—儿科]