铜对大鼠学习记忆和海马区超微结构的影响

目的观察铜负荷饮食对大鼠空间学习记忆行为和海马超微结构的影响。方法 40只雄性大鼠随机分为模型组和空白对照组各20只,采用Morris水迷宫实验测试大鼠学习记忆能力,采用原子吸收法检测肝、脑组织铜元素含量,电镜技术观察海马区超微结构变化。结果 Morris水迷宫实验:模型组大鼠在定位航行试验中平均逃避潜伏期较正常对照组显著延长,空间探索试验中穿越平台次数较正常组明显减少(P<0.01),与正常对照组比较,模型组大鼠肝、脑组织铜含量明显增加(P<0.01),海马组织内模型组大鼠神经元突触间隙明显变宽(P<0.05),突触后致密物厚度明显变薄(P<0.05)。结论铜可能通过损伤海马超微结构引起大鼠学习记忆功能障碍。

Effects of copper on learning and memory and hippocampal ultra-microstructure in rats

Objective To determine the effects of copper-overloaded diet on learning and memory and hip-pocampal ultra-microstructure of rats. Methods Forty male SD rats were random assigned to 2 control and model group, respectively. Morris water maze test was used to evaluate the learning and memory capacity. The brain and liv-er were biopsied for the measurement of copper contents. The ultra-microstructure in hippocampus were observed by using transmission electron microscope. Results The mean escape latent period was markedly prolonged and the number of traversing flat roof of the model group significantly decreased compared with those of control group （both P〈0.01）. The tissue levels of copper were increased in the model group （P〈0.01）. This was accompanied by the widen-ing of synaptic cleft and reduction in the PSD thickness （both P〈0.05） in the model group. Conclusion Copper-overloaded diet can elicit injury of the hippocampus neurons via damage of the ultra-microstructures of the hippocam-pus.