摘要目的 观察慢性不可预见性应激对大鼠认知功能和脑电生理活动的影响是否存在相关性及可能的神经电生理机制.方法 20只雄性SD大鼠随机分成对照组(n=10)和模型组(n=10).用慢性不可预见性应激刺激模型组大鼠,用主动回避行为实验检测两组大鼠脑功能,用脑电图检测大鼠脑电活动.结果 与对照组相比,模型组大鼠在主动回避行为测试的学习阶段学会躲避电击前的失败率明显减少[(42±36)%,982±30)%,P＜0.05],且脑电图频谱分析显示δ波(0.5～3Hz)的功率值增加[(47.09±22.86)μv2,(22.55±11.57) μv3,P＜0.05].模型组大鼠的主动回避行为学习阶段学会前的失败率与脑电δ波功率呈正相关(相关系数r=0.717,P＜0.05);结论慢性不可预见性应激导致大鼠的主动回避行为增强,同时脑电图δ波的功率值增加,脑认知功能与脑电活动之间存在正相关.

abstractsObjective To investigate whether there is correlation exists in the effection of chronic unpredictable stress on active avoidance behavior and electroencephalogram ( EEG) of rat. Methods Twenty male SD rats (weight～200 g) were randomly divided into control group( n= 10) and model group( n- 10). Rats in model group were subjected to chronic unpredictable stress . Active avoidance response were observed with GeminiTM avoid system and EEG power spectrum was evaluated with Powerlab system. Results The failure rate in active avoidance test was correlation with delta wave power in EEG. Compared with control group, rats in model group had reduced failure rate in active avoidance task(42 ±36)% vs (82 ±30)% , P＜0.05). The EEG power spectrum of model group rats increased in delta band((47.09 ±22.86)μV2 vs (22. 55 ± 11. 57) μV2, P＜0. 05), which had the significant difference between the two group rats. The failure rate of active avoidance task in model group rats was positive correlation with EEG power spectrum of delta wave (r = 0. 717, P ＜ 0. 05) . Conclusion Chronic unpredictable stress facilitated active avoid behavior and changed spontaneous EEG, which suggested chronic unpredictable stress actived the neurotransmitter network system involved with active avoidance task in central nervous system. Brain cognitive function correlated positively with brain electrophysiology activity measured in chronic unpredictable stress induced rat model.