铅暴露对大鼠学习记忆功能和海马CA1区LTP的影响

Effects of Lead Exposure on Learning and Memory Capability and LTP in Hippocampal CA1 Area of Rat

目的本研究观察铅对大鼠学习记忆功能和海马CA1区LTP的影响,探讨铅对学习记忆功能影响的可能机制。方法22只大鼠随机分为2组。铅暴露组每天通过饮水饲以浓度为0.05g/L醋酸铅水溶液,对照组大鼠饮用蒸馏水。28天后开始水迷宫实验。之后,通过电生理实验比较强直刺激前后海马CA1区PS幅度变化。结果在水迷宫实验中,铅暴露组大鼠寻找平台时间的缩短速度明显低于对照组,在搜索实验中错误次数明显增多。电生理实验中,铅暴露组强直刺激后平均PS幅值增至强直刺激前的(120.48±4.67)%,明显低于对照组(181.71±3.86)%。结论铅暴露明显损伤了大鼠的空间学习和记忆能力,并明显抑制了大鼠海马CA1区LTP,铅对海马LTP的抑制是其损伤学习记忆功能的可能机制之一。

Objective To observe the effects of lead exposure on learning and memory capability and LTP in hippocampal CA1 area of rat. Methods 22 SD rats were randomized into 2 groups, The rats in the lead exposure group were fed of 0.05g/L lead acetate solution, the rats in the control group were fed of distilled water. After 28 days,the learning and memory capability were detected in morris water maze, At the end of the experiment, electrophysiological method was used to observe the effects of lead on LTP in hippocampal CA1 area. Results In the Morris water maze test, the lead exposed rats displayed much longer latencies and spent less time in the target quadrant than that in control group. In the electrophysiological experiments, Average population spike amplitudes of lead exposed rats increase rate were markedly decreased. Conclusion Lead exposure significantly damage the rats spatial learning and memory capacity, and inhibited LTP in rat hippocampal CA1 area, the inhibition of LTP may play an important role in this damage.