辐射热致痛及其在镇痛药临床试验中的应用初探

应用辐射热测痛仪在恒温22℃电压5V时测得健康成年人基础痛阈和耐痛阈接近正态分布;对同一个体不同时间重复测定阈值是稳定性。将此法用于评价镇痛药对实验性疼痛的镇痛效果,结果表明,氨酚待因片(2片)能使健康受试者痛阈和耐痛阈分别提高23%和12%,与对照组比较差异有显著性(P<0.01和0.05)。盐酸丁丙诺啡峰作用时可使痛阈和耐痛阈分别提高45%和32%(P<0.01),各剂量组对抑制痛反应呈量效关系,镇痛作用持续时间超过6h。本研究认为虽然辐射热致痛法适宜评价镇痛药的镇痛效果,但是对试验结果应该进行慎重解释。

A PRELIMINARY STUDY ON THE METHOD OF RADIANT HEAT INDUCED PAIN AND ITS VALIDITY IN THE CLINICAL ASSESSMENT OF ANALGESIC DRUGS

The basic pain threshold and pain tolerance were measured by use of radiant heat stimulation in healthy volunteers, which were close to normal distribution. The stability was obtained by repeated determination for same individuals in different time. With this method, a clinical assessment of analgesic drugs was carried out among healthy volunteers. Acetaminophen-Codeine tablet ( 2 tablets ) was able to depress pain response by increasing pain threshold and tolerance of 23% and 12% ( P<0.01, P<0.05 ) respectively. Buprenor-phine hydrochloride increased pain threshold and pain tolerance by 45% and 32% C P<0.01 ) respectively at peak effect and there was a dose-effect relationship among different dose groups ( 0.lmg, 0.2mg and 0.3mg). The analgesic duration of Buprenorphine lasted more than 6 h. Results from this study suggested that the method of radiant heat stimulation is suitable for assesement of analgesic drugs, but the results should be evaluated carefully.