曲马多对福尔马林诱发大鼠脊髓背角神经元c-fos基因表达的抑制作用

Inhibitory effect of tramadol on c-fos expression induced by formalin in spinal cord dorsal horn in rats

目的 研究曲马多对疼痛刺激诱发大鼠脊髓c fos蛋白的抑制作用及其在脊髓的可能作用部位。方法 SD大鼠 6 0只 ,随机分为对照组 (N组 ,生理盐水 )、三个曲马多处理组 (T1组 1mg/kg、T2 组 10mg/kg、T3 组 2 0mg/kg)、两个吗啡处理组 (M1组 1mg/kg、M2 组 5mg/kg) ,每组各 10只。于左后足趾皮下注射 5 %福尔马林前 10分钟静脉注射上述药物。致痛 2小时后 ,取出脊髓 ,用免疫组化检测FLI阳性神经元。结果 N组FLI细胞主要分布在Ⅰ～Ⅱ及Ⅴ～Ⅵ层 ,T2 、T3 、M1和M2组FLI细胞与N组相比减少。结论 曲马多预处理能对疼痛引起的脊髓灰质背角FLI阳性神经元增多效应产生剂量依赖性的抑制作用 ;

Objective To investigate effect of tramadol on c-fos expression in spinal cord dorsal horn and its possible acting site.Methods The model was made by injection of formalin into planter surface of left hind paw.Sixty rats were randomly divided into six groups:control group(N,pretreatment with saline 2ml),three tramadol groups(T 1,T 2 and T 3,preteated with 1.0mg/kg,10mg/kg and 20mg/kg tramadol respectively) and two morphine groups(M 1 and M 2,pretreated with morphine 1.0mg/kg and 5.0mg/kg).Fos-positive neurons were identified by the immunohistochemical technique.Results The greatest density of Fos-positive neurons was located in lamine Ⅰ-Ⅱ and Ⅴ-Ⅵ In group N,pretreatment with either morphine or tramadol could produce dose depended inhibitory effect on c-fos expression.Conclusions Pretreatment with tramadol could produce dose depended inhibitory effect on c-fos expression on spinal cord dorsal horn;lamine Ⅰ-Ⅱ and Ⅴ-Ⅵ of spinal cord dorsal horn may be the key site of tramadol to modulate pain.