新生大鼠缺血低氧性脑损伤后学习记忆和海马神经元超微结构的研究

The effect of hypoxic-ischemic brain damage on long-term learning and memory abilities and ultrastructure of hippocampal CAl neuron in neonatal rats

目的 研究缺血低氧性脑损伤对新生大鼠远期学习记忆和海马CAl区神经元超微结构的影响 ,并探讨其作用机理。方法 7日龄Wistar大鼠 36只随机分为实验组和正常对照组 ,随机取 2 1只行右侧颈总动脉结扎后吸入 8%氧气 2h建立HIE模型。至 80d左右行Y迷宫测试学习和记忆能力 ,然后用透射电镜观察海马CAI区锥体神经元的超微结构变化。结果 HIE组大鼠学习和记忆能力均明显低于正常对照组 (P <0 0 1,P <0 0 5 ) ;其CAI区锥体神经元见部分核膜消失、线粒体嵴模糊、数量明显减少等超微结构改变。结论 新生期缺血低氧性脑损伤可致大鼠远期学习和记忆障碍 。

Objective To study the effects and mechanisms of hypoxic ischemic brain damage(HIBD)on long term learning and memory abilities and ultrastructure of hippocampal CAl neurons in neonatal rats.Methods 36 seven day old rats were randomly divided into the test group (n=21) and the control group (n=15).The test group was subjected to right common carotid artery ligation followed by exposure to 8% oxygen at 37℃ for 2h.When the rats were 80 days,they were given the Y maze test for learning and memory abilities;and the ultrastructure of hippocampal CAl neurons was studied by electron microscope.Results The learning and memory abilities of the hypoxic ischemic group were worse than those of the control(P<0 01,P<0 05,respectively).The nuclear membrane and mitochondria of hippocampal CAl neurons in the test group were distorted compared with those in the control group.Conclusion Hypoxic ischemic brain damage led to disorders of learning and memory in rats.It may be correlated with the changes of hippocampal CAl neurons resulting in the damage of synapse junctions and communication abilities.