中文摘要：

目的观察鞘内注射甘珀酸（CBX）对腰5脊神经切断（SNT）大鼠机械痛阈及脊髓背角星形胶质细胞标志物（GFAP）和TNF-α、IL-1β表达的影响。方法 36只成年♂SD大鼠,随机分成3组（n=12）,假手术组（Sham组）、SNT＋NS组（NS组）、SNT＋CBX（CBX组）。Sham组仅暴露腰5脊神经,不切断,NS组和CBX组切断腰5脊神经。术后10d,Sham组和NS组鞘内注射生理盐水10μl,CBX组鞘内注射甘珀酸5μg（10μl）,分别于术前1 d,术后1、3、5、7、10 d及给药后1、2、4、6 h随机取6只大鼠测损伤侧机械痛阈（MWT）,并采用免疫组化技术观察给药后2 h后损伤侧脊髓背角中GFAP表达的变化,ELISA测定损伤侧脊髓背角TNF-α和IL-1β的水平。结果 3组大鼠术前1 d,MWT差异均无显著性（P〉0.05）;Sham组术后各时间点与术前相比损伤侧MWT差异无显著性（P〉0.05）;与Sham组相比,NS组和CBX组术后1、3、5、7、10 d痛阈明显下降（P〈0.05）;NS组术后10 d给药后1、2、4、6 h,MWT与给药前无差异（P〉0.05）,但给药后2 h损伤侧脊髓背角GFAP的表达和TNF-α、IL-1β的水平较Sham组明显增高（P〈0.05）;CBX组给药后1、2、4 h损伤侧MWT较给药前明显提高（P〈0.05）,6 h无差异（P〉0.05）,给药后2 h损伤侧脊髓背角GFAP的表达和TNF-α、IL-1β的水平较NS组明显降低（P〈0.05）。结论单次鞘内注射5μg CBX可改善脊神经切断大鼠损伤侧机械痛敏行为,该效应可能与其抑制损伤侧脊髓背角星形胶质细胞的活化,减少TNF-α、IL-1β的释放有关。

英文摘要：

Aim To observe the effect of intrathecal injection of carbenoxolone（CBX） on hyperalgesia and expression of astrocytes surface marker-GFAP（glial fibrillary acidic protein） and proinflammatory cytokines as：TNF-α and IL-1β in ipsilateral spinal horns in rats with L5 spinal nerve transection（SNT）.Methods Thirty-six male Sprague-Dawley rats were randomly divided into three groups（n=12）：group Sham received sham surgery then treated with saline;group NS received SNT then treated with saline;group CBX received SNT then treated with 5 μg CBX.Treatment was undertaken with 10 μl volume as a single intrathecal injection on postoperative day 10.Mechanical withdrawl thresholds（MWT） were determined on preoperative day 1,postoperative days 1,3,5,7,10 and 1,2,4,6 h after intrathecal administration.Lumbar spinal cord was obtained 2 h after intrathecal administration to determine the expression of GFAP by immunohistology、TNF-α and IL-1β by ELISA in the ipsilateral spinal dorsal horns.Results Before surgery,there was no significant difference of the MWT among the three groups（P0.05）.Compared with the MWT before sugery,the value on postoperative days in group Sham revealed no marked difference（P0.05）.Compared with group Sham,the group NS and CBX showed a significant decrease of MWT on postoperative days 1,3,5,7,10（P0.05）.Compared with the MWT 1 h before intrathecal administration on day 10,the values at 1,2,4,6 h after administration of group NS revealed no marked difference,but GFAP,TNF-α and IL-1β at 2 h after administration in the ipsilateral spinal dorsal horn were significantly increased compared with those in group Sham.Compared with the MWT 1 h before injection in group CBX,the values at 1,2,4 h after administration were signficantly increased（P0.05）,but at 6h showed no significant difference（P0.05）.Furthermore,the expression of GFAP,TNF-α and IL-1β in the spinal dorsal horn was significantly decreased compared with those in group NS.Conclusion Single intrathecal injectio