海马体亚惊厥电刺激对大鼠情绪及空间学习与记忆的影响。

Effects of subconvulsive electrical stimulation to the hippocampus on emotionality and spatial learning and memory in rats.

作者信息

Wang Qingsong, Wang Zhengguo, Zhu Peifang, Jiang Jianxin

机构信息

Research Institute of Surgery, Daping Hospital, Third Military Medical University, Chongqing 400042, China.

出版信息

Chin Med J (Engl). 2003 Sep;116(9):1361-5.

PMID:14527366

Abstract

OBJECTIVE

To observe the effects of repeated subconvulsive electrical stimuli to the hippocampus on the emotional behavior and spatial learning and memory ability in rats.

METHODS

One hundred and eight male Wistar rats were randomized into 3 groups. Animals in group SE (n = 42) were given subconvulsive electrical stimulation to the hippocampus through a constant pulsating current of 100 mu A with an intratrain frequency of 25 Hz, pulse duration of 1 millisecond, train duration of 10 seconds and interstimulus interval of 7 minutes, 8 times a day, for 5 days. In the electrode control group or CE group (n = 33), animals were implanted with an electrode in the hippocampus, but were not stimulated. Group NC (n = 33) animals received no electrode or any stimulation. The emotional behavior of experimental rats was examined by activity in an unfamiliar open field and resistance to capture from the open field, while the spatial learning and memory ability was measured during training in a Morris water maze.

RESULTS

The stimulated rats tested 1 month after the last round of stimulation displayed substantial decreases in open field activity (scale: 10.4 +/- 2.3, P < 0.05) and increases in resistance to capture (scale: 2.85 +/- 0.56, P < 0.01). The amount of time for rats in group SE to find the platform (latency) as a measurement for spatial bias was prolonged (29 +/- 7) seconds after 15 trials in the water maze, P < 0.05). The experimental rats swam aimlessly in all four pool quadrants during the probe trial in the Morris water maze.

CONCLUSIONS

Following repeated subconvulsive electrical stimuli to the hippocampus, rats displayed long-lasting significant abnormalities in emotional behavior, increased anxiety and defensiveness, enhanced ease to and delayed habituation to startlement, transitory spatial learning and memory disorder, which parallels many of the symptoms in posttraumatic stress disorder patients.

摘要

目的

观察对大鼠海马进行反复亚惊厥性电刺激对其情绪行为及空间学习和记忆能力的影响。

方法

108只雄性Wistar大鼠随机分为3组。海马亚惊厥电刺激组（SE组，n = 42）通过100 μA恒定脉动电流对海马进行亚惊厥电刺激，串内频率25 Hz，脉冲持续时间1毫秒，串持续时间10秒，刺激间隔7分钟，每天8次，共5天。电极对照组（CE组，n = 33）大鼠海马植入电极但不进行刺激。正常对照组（NC组，n = 33）大鼠不植入电极且不接受任何刺激。通过在陌生旷场中的活动及对旷场抓捕的抵抗来检测实验大鼠的情绪行为，同时在Morris水迷宫训练期间测量其空间学习和记忆能力。

结果

在最后一轮刺激后1个月进行测试时，受刺激大鼠的旷场活动显著减少（评分：10.4 ± 2.3，P < 0.05），对抓捕的抵抗增加（评分：2.85 ± 0.56，P < 0.01）。水迷宫中，SE组大鼠找到平台的时间（潜伏期）作为空间偏向的测量指标，在15次试验后延长（29 ± 7）秒，P < 0.05）。在Morris水迷宫的探索试验中，实验大鼠在四个泳池象限中无目的地游动。