应激诱导小鼠杏仁核theta波段下调介导焦虑反应

Chronic Stress Affects the Theta Activity in BLA to Induce the Stress Response in Mice

慢性应激能引发诸多情绪行为的改变,诱导产生广义焦虑症、抑郁症、双极紊乱等情绪障碍性疾病。慢性应激首先引起焦虑情绪处理相关核团前额叶-杏仁核-腹侧海马区神经活动的功能性的改变,然后导致这些核团的结构发生改变。慢性应激造成杏仁核基底外侧核的锥体神经元的树突脊数量增多,谷氨酸能神经元的兴奋性投射增强,γ-氨基丁酸能神经元的抑制性投射减弱,导致焦虑样行为症状。由于慢性应激对于这些参与情绪调控的关键核团的神经活动的功能改变尚不明确,所以我们建立小鼠慢性应激的模型,分别在对照鼠和模型鼠的杏仁核基底外侧核及海马CA3区记录局部场电位,分离局部场电位的alpha、beta、delta、theta、gamma波段,分析其局部场电位各个波段的绝对功率和相对功率的差异。结果显示:慢性应激造成小鼠杏仁核基底外侧核的局部场电位在5个脑电波段的绝对功率均具有上调趋势,其中delta波段上调显著;进一步分析局部场电位的相对功率发现,慢性应激造成delta波段的相对功率显著上调,而theta波段的相对功率显著下调。

Chronic exposure to stress triggered many dysfunctional emotional behaviors,like generalized anxiety disorder,depression and bipolar disorder.Prolonged stress led to structural changes in the prefrontal cortex-amygdala-ventral hippocampus emotional circuit and thus exerted anxiety behavioral phenotypes.But the alteration of neural activity for those nucleus that involved in emotional regulation is not clear.So chronic stress model in mice was established local field potential（LFP）were recorded from the basolateral amygdala（BLA）and hippocampal CA3 respectively in freely exploring mouse and separated the signals into alpha,beta,and delta,theta,gamma frequency bands.In contrast to the control groups,in BLA,stress induced a trend of increase of LFP absolute power at these five bands,the increase at delta band was significant.Through further analysis of the LFP relative power,it showed that there was a distinct increase at delta band and a significant decrease at theta band in stressed mice.