N-乙酰-5-甲氧色胺对创伤痛的影响及作用部位分析  

A research on the effects of melatonin on post-injury pain and its possible action site

作　　者：李淑慧[1] 胡德耀[1] 李晓辉[2] 王正国[1] 

机构地区：[1]第三军医大学大坪医院野战外科研究所二室,重庆400042 [2]第三军医大学基础部药理教研室

出　　处：《中国康复医学杂志》2003年第9期526-528,共3页Chinese Journal of Rehabilitation Medicine

摘　　要：目的:研究N-乙酰-5-甲氧色胺对创伤痛的影响,并对其可能作用部位进行分析。方法:以大鼠截肢结合50℃热水刺激举尾作为创伤痛模型,大鼠创伤后即刻、1d、2d、3d腹腔注射不同剂量的Mel(30,60,120mg/kg)、Pt20mg/kg、Mel+Pt(10+10mg/kg)及溶媒,于创伤前及最后一次给药后20min、40min、80min、120min观察痛阈(50℃刺激举尾潜伏期)变化情况。观察创伤后3d侧脑室注射Mel(0.25、0.5、1.0mg/kg)后20min、40min、80min、120min的痛阈变化情况。结果:创伤后3d痛阈降至最低,7d恢复至正常。腹腔注射Mel(30—120mg/kg)或侧脑室注射Mel(0.25—1.0mg/kg)均剂量依赖性地增加了创伤大鼠的痛阈,且于给药后40min达高峰,持续至120min仍有效。Mel(10mg/kg)与Pt(10mg/kg)合用,能明显提高小鼠痛阈。结论:Mel对创伤痛具有良好的镇痛作用,其主要作用部位在中枢。Mel与哌替啶有明显协同镇痛效应。Objective:To investigate the antinociceptive effects of Melatonin(Mel)on pain in post-injury rats and to explore the possible site of the analgesic action of Mel.Method:Rat trauma pain model was established in Wis-tar rats by limb amputation with the determination of tail-flick latency to ho t water at50℃.The animals were in-traperitoneally(i.p.)injected Mel(30,60,120m g/kg),pethidine(Pt,20mg/kg),Mel+Pt(10+10mg/kg)and solvent respe ctively at0min, 1d,2d,3d post-injury.The pain thresholds were measured at20min,40min,80min,120mi n after the drugs used at3d.In addition,the pain thresholds were also measured a t20min,40min,80min,120min after i.c.v Mel(0.25?0.5?1.0mg/kg)one time at3d in i njuried rats.Result:The pain thresholds reached to the lowest point at3d post-in jury,and then returned to the normal level at7d post-injury.Both i.p.Mel(30-120 mg/kg)or i.c.v.Mel(0.25-1.0mg/kg)can increase the pain thresholds in injuried r ats in a dose-dependent manner,and the analgesic effects of which reached to cli max at40min and lasted until120min after Mel used.Coadministration of Mel(10mg/k g)with Pt(10mg/kg)can also enhance the pain thresholds obviously.Conclusion :Mel has obvious antinociceptive effect on pain in post-injury rats,and the central n ervous system(CNS)may be the primary site for Mel to elicit the re-sponse.Moreo ver,there is a marked synergistic effect between Mel and Pt.

关 键 词：N-乙酰-5-甲氧色胺 创伤 疼痛 镇痛作用 哌替啶 

分 类 号：R641[医药卫生—外科学] R441.1[医药卫生—临床医学]