瑞芬太尼诱发痛觉过敏在切口痛的发生机制研究

A Study on Mechanical of Incisional Pain of Hyperalgesia Induced by Remifentanil

目的观察大鼠脊髓谷氨酸转运体-1(GLT-1)和谷氨酰胺合成酶(GS)硝基化在切口痛-瑞芬太尼痛觉过敏中的作用,旨在探讨其发生机制。方法选取SD大鼠40只,随机分为对照组(C组)、切口痛组(I组)、瑞芬太尼组(R组)、瑞芬太尼+切口痛组(RI组),每组10只。C组和I组尾静脉输注生理盐水; R组和RI组尾静脉输注瑞芬太尼。测定4组静注前24 h、静注后2、6、24和48 h的机械刺激缩足阈值(PWT)、热刺激缩足阈值(PWL)。检测并比较4组脊髓GLT-1、GS总蛋白(tGLT-1和tGS)和硝基化蛋白(nGLT-1和nGS)表达水平。结果 I组、R组和RI组PWT、PWL低于或短于C组,且RI组低于或短于I组、R组(P <0. 05)。RI组、R组和I组脊髓tGLT-1、tGS蛋白表达低于C组,且RI组低于I组、R组(P <0. 01),nGLT-1、nGS蛋白表达、nGLT-1/tGLT-1比值和nGS/tGS比值均高于C组,且RI组高于R组、I组(P <0. 01)。结论大鼠切口痛-瑞芬太尼痛觉过敏的形成可能与脊髓背角GLT-1和GS总蛋白表达下调,硝基化的GLT-1和GS蛋白表达上调,GLT-1和GS硝基化蛋白/总蛋白比值增加有关。

Objective To observe effects of nitrated glutamate transporter-1(GLT-1)and glutamine synthetase(GS)in spinal cord in incisional pain(IP)-Remifentanil-induced hyperalgesia in rats in order to investigate its pathogenesis.Methods A total of 40 SD rats were randomly divided into control group(C group,n=10),incision pain group(I group,n=10),Remifentanil group(R group,n=10)and Remifentanil+incision pain group(RI group,n=10).Saline was infused into caudal vein in group C and I,while Remifentanil was infused into caudal vein in group R and RI.Among four groups,values of mechanical pain withdrawal threshold(PWT)and thermal paw withdraw latency(PWL)were detected in 24 h before intravenous injection and in the 2 nd,6 th,24 th and 48 th h after intravenous injection,and expressions of total GLT-1 and GS proteins(tGLT-1 and tGS)and nitrated GLT-1 and GS proteins(nGLT-1 and nGS)in spinal cord were detected and compared.Results Compared with those in group C,PWT and PWL values were significantly lower,while the values in group RI were significantly lower than those in group I and R(P<0.05).Expressions of tGLT-1 and tGS proteins in spinal cord in group RI,R and I were significantly lower than those in group C,and the expressions in group RI were significantly lower than those in group I and R nGLT-1,nGS protein,nGLT-1/tGLT-1 ratio and nGS/tGS ratio in RI group were higher than those in R group and I group(P<0.01).Values of nGLT-1 and nGS protein expressions,nGLT-1/tGLT-1 ratio and nGS/tGS ratio in spinal cord in group RI,R and I were significantly higher than those in group C,and the values in group RI were significantly higher than those in group R and I(P<0.01).Conclusion Pathogenesy of IP-Remifentanil-induced hyperalgesia in rats may be related to decrease of total GLT-1 and GS protein expressions,up-regulation of nitrated GLT-1 and GS protein expressions and increase of nitrated/total GLT-1 and GS protein ratios in spinal cord of rats.