电针抑制大鼠吗啡条件性位置偏爱

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。

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

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.