电针抑制大鼠吗啡条件性位置偏爱

Electroacupuncture suppresses morphine-induced conditioned place preference (CPP) in rats

目的 :观察不同频率电针刺激能否抑制大鼠吗啡条件性位置偏爱 (conditionedplacepreference ,CPP)的表达。方法 :采用计算机自动控制的三室迷宫CPP系统 ,第 1天测试天然偏爱 ;第 2至 5天进行条件训练 (吗啡 4mg·kg-1,i.p ,对照组给予等量的生理盐水 ) ;第 6天在无药状态下观察大鼠在伴药盒的停留时间。于CPP检测后2 4h ,分别给予大鼠 2Hz或 10 0Hz的电针刺激 ,每天 1次 ,连续 3天 ,最后一次电针结束后 2 4h测定大鼠在伴药盒停留时间。结果 :实验组大鼠在伴药盒的偏爱分数明显高于对照组。 2Hz及 10 0Hz电针均能明显降低CPP大鼠在原伴药盒的偏爱分数。结论 :多次 2Hz及 10 0Hz电针均能抑制大鼠吗啡CPP表达 ,两种频率的抑制效应差异无显著性。

Objective: To examine the effects produced by electroacupuncture (EA) of different frequencies on the expression of morphine conditioned place preference (CPP) in rats. Methods: SD rats were given 4 days consecutive trials in a computerized three chamber 'unbiased' CPP apparatus. Twenty four hours later, the time spent on drug pairing compartment of the rat was examined. Rats trained with CPP paradigms were then given EA of 2 Hz or 100 Hz once a day for 3 days. Twenty four hours after the final EA session, they were again put to the CPP chamber, and the time spent on drug pairing compartment was measured. Results: Rats receiving morphine at a dose of 4 mg·kg -1 (i.p.) showed significantly enhanced preference scores in drug pairing side than that of the control group. In other words, rats preferred the drug pairing environment to the nondrug pairing place. In addition, rats that received treatment with EA of 2 Hz or 100 Hz spent significantly less time on the drug pairing side than that of the CPP control group. Conclusion: Morphine induced CPP paradigms were stably established in rats using a computer controlled 3 chamber CPP experimental system. The expression of CPP could be significantly inhibited by multiple treatments with EA of either 2 Hz or 100 Hz.