Objective: It has been shown that there are extensive interactions between the central nervous system and the immune system. The present study focused on the effects of lipopolysaccharide (LPS) on memory retrieval, to explore the interaction between immune activation and memory.
Methods: C57BL/6J mice (8 weeks old) were first trained in the Morris water maze to reach asymptotic performance. Then mice were tested 24 h after the last training session and LPS was administered (1.25 mg/kg, i.p.) 4 h prior to the testing. The retrieval of spatial memory was tested by probe trial, and the time spent in the target quadrant and the number of platform location crosses were recorded. ELISA was performed to detect interleukin-1β (IL-1β) protein level in the hippocampus of mice tested in the water maze.
Results: Although LPS induced overt sickness behavior and a significant increase in the level of IL-1β in the hippocampus of mice, there was no significant difference in the time spent in the target quadrant or in the number of platform location crosses between LPS-treated and control groups in the probe trial testing.
Conclusion: Immune activation induced by LPS does not impair the retrieval of spatial memory.
目的: 神经系统和免疫系统之间存在广泛的相互作用。 许多研究表明, 细菌脂多糖(lipopolysaccharide, LPS)或白介素1β 引起的免疫激活会造成学习记忆的损伤。 但也有一些研究报道免疫激活对学习记忆几乎没有影响。 因此, 免疫激活与学习记忆损伤之间的关系尚不十分清楚。 本研究旨在检测LPS 对空间记忆提取的影响, 探讨免疫激活与记忆之间的相互作用。
方法: 先在水迷宫中训练 琪琪8 周龄C57BL/6J 系小鼠, 随后小鼠腹腔注射LPS 并进行空间觅向能力测试。 记录小鼠在目标象限游泳的时间和穿过原平台位置的次数, 以判断动物记忆提取再现能力。 用酶联免疫法检测小鼠海马中白介素1β 的水平。
结果: LPS 能引起小鼠产生明显的病态行为, 并导致海马中白介素1β的水平显著升高。 注射LPS的小鼠在目标象限游泳的时间以及穿越逃生台位置的次数与对照组小鼠相比没有显著差异。
结论: LPS 引起的免疫激活并不损害空间记忆的提取。