突触功能障碍大鼠模型EE G 频域特征

本文旨在探讨突触功能障碍大鼠模型在额叶、颞叶和海马这些与认知功能有关的脑区EEG频域特征。先用海马CA1区Aβ1-40加微量注射法制备突触功能障碍模型，用Morris水迷宫行为学测试系统检测其学习记忆能力；然后记录上述脑区的EEG并做频谱分析。结果显示：（1）模型组在第3,4、5、6训练时间段的平均逃避潜伏期较正常组明显延长，和第2训练时间段的相比较，正常组第5训练时间段平均逃避潜伏期明显缩短，模型组到第7训练时间段平均逃避潜伏期开始明显缩短（P〈0．05）；撤去平台后，模型组在原平台所在象限的时间百分比明显降低（P〈0．05）。（2）模型组的EEG表现为α节律慢化，功率下降，其主峰频率左移2Hz，并且额叶、颞叶和海马的δ波和θ波功率不同程度地增高。由此Aβ1-40微量注射法成功制备了突触功能障碍大鼠模型。该模型大鼠的学习记忆能力降低，其频谱特征表现为α节律慢化，功率下降或消失，慢波（δ波和θ波）活动增多，功率不同程度地增高。这些与阿尔茨海默病（Alzheimer’s disease，AD）的EEG一致，可为以后对突触功能障碍时受累皮层进行深入的可塑性和神经再生的研究提供电生理基础。

EEG Characteristics in Frequency Domain in Synaptic Dysfunction Rat Model

EEG characteristics in frequency domain were investigated in the frontal lobe, occipital lobe and hippocampus, i.e. cognition - related cortex of synaptic dysfunction model rat, providing electrophysiological basis for further study on plastic extent and nerve regeneration of the damaged neurons. Synaptic dysfunction model was made via microinjecting β - amyloid protein1 - 40 (Aβ1 - 40) into hippocampal CA1 area of rat. Morris water maze behavioral test was performed to evaluate the learning and memory function of model group. Then EEG in the above areas for two groups were recorded. The spectrum for two groups was performed and the characteristics in frequency domain were analyzed. The results showed: (1) The average escape latency in 3rd, 4th, 5th and 6th training times of model group are higher than those of normal. The average escape latency of normal group in 5th training time decreased more markedly than that in 2nd training time, while that of model group in 7th training time decreased more remarkably than that in 2nd training time (P ＜0.05). Without platform, the platform quadrant time percentage of model group was lower than the control (P ＜0.05). (2) Alpha rhythm in EEG of model rat was slowing down; alpha- band power decreased with peek frequency left shifted nearly 2Hz. And the power of delta - band and theta - band in frontal lobe, occipital and hippocampus all increased with different extent. The synaptic dysfunction model rats were made successfully by microinjecting Aβ1 - 40 method. The model rats show the decreased learning and memory dysfunction. EEG frequency spectrum features in model rat show slower alpha rhythm with power amplitude lower or loss, slow waves (delta and theta wave) increasing with higher power amplitude. These can be consistent with the EEG of Alzheimer's disease patients, which can provide electrophysiological basis for further plasticity and nerve regeneration study on the impaired cortex with synaptic dysfunction.