消退训练对创伤后应激障碍模型大鼠的影响

Effects of extinction training on model rats with post-traumatic stress disorder

目的:探讨消退训练(extinction training,ET)对创伤后应激障碍(PTSD)模型大鼠条件性恐惧记忆以及空间学习记忆能力的影响。方法:通过重复给予"声音-电击"配对刺激建立PTSD大鼠模型,将模型分层随机分为空白对照组和消退训练组(ET组)。ET组进行14 d的消退训练(情景暴露)干预。第2、4、8、14天在恐惧监测系统中检测大鼠的木僵反应(代表条件性恐惧记忆),第15～21天在Morris水迷宫中检测大鼠的学习记忆能力。结果:与对照组相比,ET干预使模型大鼠的木僵反应明显受抑(P<0.01),且显著缩短大鼠的定位航行测试的逃避潜伏期(P<0.05)。结论:消退训练可促进PTSD大鼠的条件性恐惧记忆的消退,且改善大鼠的空间学习能力。

Objective：To investigate the effects of extinction training（ET） on fear-conditioning memory and the ability of spatial learning and memory in model rats with post-traumatic stress disorder（PTSD）.Methods：PTSD models of rats were prepared by repeating pairings of ＂sound and shock＂ stimuli.By stratified random sampling,the model rats were divided into control group（n=7） and ET group（n=6）.During the intervention with ET（context exposure） in a session of 14 days,the freezing response,representing fear-conditioning memory,was observed at day 2,4,8 and 14,respectively,using a freezing monitor system,and the spatial learning and memory function was determined between the 15th 21st day by Morris water maze.Results：The intervention with ET enabled significant inhibition of freezing response（P〈0.01） and shortened the escape latency in place navigation test of model rats as compared with the control group（P〈0.05）.Conclusion：ET can promote the diminution of fear-conditioning memory response,and improve the spatial learning ability in model rats with PTSD.