脑室注射环—磷酸鸟苷(cGMP)对大鼠电针镇痛的影响

<正> 近十余年来,对于环-磷酸鸟苷(cGMP)在中枢神经系统中的机能作用引起了人们的注意.有报导 cGMP 具有镇痛性质,并假设 cGMP 或许是一种或一种以上的神经递质的调节者。本工作是观察脑室注射cGMP 对针刺镇痛的影响,并探索它与乙酰胆碱及阿片样物质之间可能存在的关系.

THE EFFECT OF INTRAVENTRICULAR INJECTION OF cGMP ON ACUPUNCTURE ANALGESIA OF RATS

The purpose of this study is to observe the effects of intraventricularinjection(IVT)of cGMP on acupuncture analgesia(AA)and its relationshipwith acetylcholine and endogenous opiate like substances.The followingresults have been obtained.1.After the intraventricular injection of cGMP(400μg)pain thresho-lds of rats were markedly elevated (47%～63%).During continuous electro-acupuncture for thirty minutes,the average pain threshold increased by47%.Intraventicular injection of cGMP associated with additional electro-acupuncture elevated markedly Pain thresholds(130%).The effect wasmore that of arithmetic sum of cGMP plus electro-acupuncture.Theseresults indicated that cGMP enhanced the effects of AA.2.The effects of AA decreased by 18% at 3 hours after IVT of hemi-cholinium-3(50μg).On the basis of that,cGMP raised the effects of AA by42%,but the effect failed to reach the original level.The result suggestedthat the enhancement of cGMP on AA could be partially antagonized byhemicholinium-3.3.The effect of AA of rats could not be blocked by the IVT ofnaloxone(30μg).When cGMP was used in combination with naloxone,the reenforce effect of cGMP on AA was not shown.The results suggestedthat the enhancement action of cGMP on AA could be antagonized by bloc-king the opiate receptor with naloxone.