恐惧记忆的形成对大鼠内侧前额叶皮层ECoG的影响

黄思佳，随力，任杰，彭彬彬，宋小金

上海理工大学 医疗器械与食品学院(上海，200093)

上海市教委科研创新项目(12ZZ143)

通信作者：随力，教授，E-mail：lsui@usst.edu.cn

【摘要】目的记录并分析大鼠在穿梭实验恐惧记忆形成前后内侧前额叶皮层的皮层脑电(Electrocorticogram，ECoG)的变化特征，揭示恐惧记忆的形成对内侧前额叶皮层ECoG的影响。方法通过穿梭实验诱导出大鼠对厌恶刺激的恐惧记忆，在恐惧记忆形成前后分别记录大鼠处于清醒和浅麻醉状态下内侧前额叶皮层的ECoG，分析ECoG频率谱、功率谱的变化特征。结果不论大鼠是处于清醒状态还是浅麻醉状态，恐惧记忆形成前后ECoG的总功率没有显著性差异(P>0.05)。尽管恐惧记忆的形成对于浅麻醉状态下的ECoG的频率谱没有显著性改变(P>0.05)，但恐惧记忆的形成对于清醒状态下的ECoG的频率谱具有显著性的影响(P<0.05):表现为θ波比例显著减少(P<0.05)，β波比例显著增加(P<0.05)。实验结果提示穿梭实验恐惧记忆的形成使清醒状态下的大鼠的内侧前额叶皮层处于兴奋状态。

【关键词】恐惧记忆；ECoG；大鼠；穿梭实验；内侧前额叶皮层

doi:10.3969/j.issn.1674-1242.2015.02.006

基金项目：国家自然科学基金(11179015, 51173108)；

作者简介：黄思佳，硕士研究生，E-mail:18914499152@163.com

【中图分类号】R319

【文献标志码】A

文章编号：1674-1242(2015)02-0086-05

Abstract【】ObjectiveThe aim of this study is to investigate the effects of fear memory formation on electrocorticogram (ECoG) in rat prefrontal cortex.MethodsShuttle box test was used to induce fear memory in rats. Electrophysiological ECoG recordings of rat prefrontal cortex were monitored before and after fear memory forming in the awaked and the anesthetized condition, respectively. The total power spectra and the frequency spectra of these ECoG were analyzed and compared.ResultsFear memory formation did not significantly alter the total power of ECoG in the prefrontal cortex, whether in the awaked or in the anesthetized rats (P>0.05). Furthermore, in the awaked rats, significant differences in the frequency distribution of ECoG were found following fear memory formation relative to before memory formation, with the evidence that the ratios of θ wave is decreased and the ratios of β wave is increased(P<0.05). Whereas, in the anesthetized rats, fear memory formation failed to affect the frequency spectra of ECoG in the prefrontal cortex (P>0.05). These findings indicated that fear memory formation excited the prefrontal cortex in the awaked rats.

收稿日期：(2015-03-15)

Effects of Fear Memory Formation on ECoG in Rat Prefrontal Cortex

HUANG Sijia, SUI Li, REN Jie, PENG Binbin, SONG Xiaojin

School of Medical Instrumentation and Food Engineering,

University of Shanghai for Science and Technology (Shanghai, 200093)

【Key words】fear memory，electrocorticogram，rat，shuttle box test，prefrontal cortex

0　引言

将电极植入到大脑皮层的特定区域而记录到的脑电图，即为皮层脑电图(Electrocorticogram, ECoG)。ECoG能直接反映大脑局部的电活动，信噪比高。使用ECoG电极，对大脑的影响比较小，不会损伤脑组织。目前ECoG的研究主要在癫痫患者或者动物身上进行研究。

学习与记忆是生物体生存的必要能力。对此研究不仅需要行为方面的研究，也依赖于在记忆过程中分子事件的细致分析[1]。条件性恐惧记忆是一种较重要的记忆类型，适当的恐惧可以帮助人们趋利避害，保护自己[2]。而紊乱……