To investigate the exercise intensity effects on rats' memory and learning, animals were divided into control, moderate training (MT), and overtraining (OT) groups. At training last week, learning and memory was assessed using Morris water maze (MWM) and passive avoidance (PA) tests. Finally, the rat's brains were removed for evaluating oxidative stress and inflammatory cytokines. Overtraining impaired animal's performance in MWM and PA tests. In MT group, hippocampal levels of interleukin 1 beta (IL-1β) and malondialdehyde (MDA) increased, and thiol contents in hippocampal and cortical tissues decreased compared to control. In OT group, tumor necrosis factor α, IL-1β, and C-reactive protein hippocampal levels increased, MDA and nitric oxide metabolite in hippocampal and cortical tissues increased, thiol contents, catalase and superoxide dismutase activity in hippocampal and cortical tissues decreased compared to control and MT groups. Overtraining might lead to learning and memory impairment by increasing the inflammatory cytokine and oxidative stress markers.

中文翻译：

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适度运动和过度训练对大鼠学习和记忆，海马炎性细胞因子水平以及脑氧化应激指标的影响。

为了研究运动强度对大鼠记忆和学习的影响，将动物分为对照组，中度训练（MT）和过度训练（OT）组。在上周的培训中，使用莫里斯水迷宫（MWM）和被动回避（PA）测试对学习和记忆进行了评估。最后，将大鼠的大脑取出以评估氧化应激和炎性细胞因子。在MWM和PA测试中过度训练会损害动物的表现。与对照组相比，MT组的海马白介素1β（IL-1β）和丙二醛（MDA）水平升高，海马和皮质组织中的硫醇含量降低。在OT组中，海马和肿瘤组织中的肿瘤坏死因子α，IL-1β和C反应蛋白水平增加，海马和皮质组织中的MDA和一氧化氮代谢产物增加，硫醇含量，与对照组和MT组相比，海马和皮质组织中的过氧化氢酶和超氧化物歧化酶活性降低。过度训练可能会通过增加炎症细胞因子和氧化应激标志物而导致学习和记忆障碍。