Objective To investigate the mechanism of Toll like receptor 4 (TLR4)uclear factor κB (NF-κB) signal pathway in rats with incisional pain.Methods One hundred healthy adult male Sprague-Dawley (SD) SPF rats of 20 weeks old were selected to establish incision pain models.Before operation and after operation for 0.5 h,1 h,2 h,8 h,12 h,1 d,2 d,3 d,5 d,7 d,the mechanism withdraw threshold (MWT) in non-operative side and operative side of rats were detected by electronic yon Frey pressure pain threshold detector.Before operation and after operation for 2 h,8 h,1 d,2 d,3 d,5 d and 7 d,the expression of TLR4,NF-κB,interleukin 1 β (IL-1 β) and tumor necrosis factor α (TNF-α) in the spinal cord were detected by real-time fluorescence quantitative PCR (real-time PCR).Results After operation,the MWT in the operative side of rats was lower than that before operation,which was the lowest after operation for 2 h,then increased gradually,and they were significantly lower than those of non-operative side (P ＜ 0.05).After operation,the expression levels of TLR4,NF-κB,IL-1β and TNF-α in spinal cord of rats were increased compared with those before operation,which of postoperative 2 h,8 h,1 d,2 d and 3 d had statistically significant differences compared with those before operation (P ＜ 0.05),which of postoperative 5 d and 7 d had no statistically significant differences compared with those before operation (P ＞ 0.05).The expression levels of TLR4 and NF-κB in the spinal cord,reached the highest after operation for 1 d,and the expression levels of IL-1β and TNF-α reached the highest after operation for 8 h.Pearson correlation analysis showed that there was a negative correlation of MWT in op erative side with the expression of TLR4 and NF-κB (r =-0.473,P ＜ 0.05,r =-0.398;P ＜ 0.05),the TLR4 levels in spinal cord of rats were positively correlated with the expression levels of IL-1 β and TNF-α (r =0.302,P ＜ 0.05;r =0.538,P ＜ 0.05),and the NF-κB levels in spinal cord of rats were positively correlated with the expression levels of IL-1β and TNF-α (r =0.283,P ＜ 0.05;r =0.467,P ＜ 0.05).Conclusion The signal pathway of TLR4/NF-κB in spinal cord of rats with incisional pain is activated,the expression levels of TLR4 and NF-κB are increased,and the expression levels of downstream inflammatory cytokines IL-1β and TNF-α are up-regulated,which is involved in the regulation process of incisional pain.%目的 探讨脊髓Toll样受体4(TLR4)/核因子κB(NF-κB)信号通路在切口痛大鼠中的作用机制.方法 选取20周龄的SD健康成年雄性SPF级大鼠100只,建立大鼠切口痛模型,于术前和术后0.5 h、1h、2h、8h、12h、1d、2d、3d、5d、7d,采用电子von Frey压力测痛仪检测大鼠非术侧和术侧的机械缩足反应阈值(MWT);于术前和术后2h、8h、1d、2d、3d、5d和7d采用实时荧光定量PCR(Real-time PCR)法检测脊髓TLR4、NF-κB、白介素1β、(IL-1β)、肿瘤坏死因子α(TNF-α)的表达水平.结果 术后,大鼠术侧的MWT较术前降低,术后2h时最低,之后逐渐升高,且显著低于非术侧(P＜0.05).术后,大鼠脊髓TLR4、NF-κB、IL-1β、TNF-α的表达水平较术前升高,且术后2h、8h、1d、2d和3d与术前比较差异有统计学意义(P＜0.05),术后5d和7d与术前比较差异无统计学意义(P＞0.05),术后1d脊髓TLR4、NF-κB表达水平达到最高,术后8h脊髓IL-1β、TNF-α表达水平达到最高.采用Pearson相关性分析结果显示,大鼠术侧MWT与TLR4和NF-κB表达水平呈负相关(r=-0.473,P＜0.05;r=-0.398,P＜0.05),大鼠脊髓TLR4与IL-1β和TNF-α表达水平呈正相关(r=0.302,P＜0.05;r=0.538,P＜0.05);大鼠脊髓NF-κB与IL-1β和TNF-α表达水平呈正相关(r=0.283,P＜0.05;r=0.467,P＜0.05).结论 切口痛大鼠脊髓TLR4/NF-κB信号通路被激活,TLR4、NF-κB表达水平升高,并上调下游炎性因子IL-1β、TNF-α的表达水平,参与切口痛的调控过程.
展开▼
