吗啡急性戒断大鼠边缘前皮层无线遥测脑电活动的研究

Research on wireless telemetry electrical activity in prelimbic cortex of acute morphine withdrawal rats

目的探讨吗啡急性戒断大鼠边缘前皮层(prelimbic cortex,PrL)脑电活动在吗啡成瘾机制中的作用。方法将大鼠随机分为吗啡实验组和生理盐水对照组。进行脑立体定位电极埋藏手术,建立吗啡依赖大鼠条件性位置偏爱(conditioned place preference,CPP)模型。测试各组大鼠的CPP行为,同时遥测分析不同行为状态下PrL的脑电活动。结果实验组大鼠戒断d 1、d 3,在白箱内停留时间明显延长(组间、组内比较)。与对照组相比,实验组大鼠戒断d 3,在黑白箱停留及黑-白箱穿梭时,PrL脑电β波明显增加,δ波明显减少;当白-黑箱穿梭时,β波明显减少,δ波明显增加;α波及θ波在各种行为状态下,组间比较差异均无显著性。结论吗啡急性戒断大鼠觅药行为的产生伴随着PrL脑电β波及δ波的特异性改变,提示PrL脑电改变可能与吗啡依赖大鼠觅药动机形成有关。

Aim To discuss the role of electrical activ- ity in prelimbic cortex （PrL） of acute morphine with- drawal rats in morphine addiction mechanism. Meth- ods The rats were randomly divided into morphine experimental group and normal saline control group. After the brain stereotaxic electrode-embedding opera- tion, the conditioned place preference （CPP） model of morphine dependent rats was established. The changes of CPP behavior in rats were tested. Meanwhile, the telemetry electrical activity in PrL of rats was recorded and analyzed in different behavioral state. Results On withdrawal d 1 and d 3, the residence time of ex- perimental group in white box was prolonged obviously （comparison within the group, comparison between groups）. Compared with control group, on withdrawal d 3, the electrical activity in PrL of experimental group showed that： when the rats stayed in black box, white box, or shuttled from black to white box, β wave in- creased obviously, and δ wave decreased obviously. However, when the rats shuttled from white to black box, β wave decreased significantly, and δ wave in- creased significantly. The changes of α wave and θ wave had no significant difference in various kinds of behavioral state. Conclusions The specific changes of β wave and δ wave＇ in PrL are accompanied by gen- eration of drug seeking behavior in acute morphine withdrawal rats. The changes of electrical activity in PrL are possibly relevant to formation of drug seeking motive in morphine dependent rats.