中文摘要：

目的 评价c-Jun氨基末端激酶（JNK）信号转导通路在利多卡因诱发大鼠脊髓神经毒性中的作用.方法 成年雄性SD大鼠72只,体重220 ～ 260 g,采用随机数字表法分为6组（n=12）：对照组（Ⅰ组）不做任何处理；假手术组（Ⅱ组）仅行鞘内置管术；JNK抑制剂组（Ⅲ组）和二甲基亚砜（DMSO）组（Ⅳ组）分别鞘内注射JNK抑制剂SP600125 25μg和DMS0 20 μl;10％利多卡因组（Ⅴ组）鞘内注射10％利多卡因20 μl; JNK抑制剂＋10％利多卡因组（Ⅵ组）先鞘内注射SP600125 25 μg,30 min后鞘内注射10％利多卡因20μl.于鞘内置管前（T0）、鞘内给药前（T1）、鞘内给药后4、8、12 h、1、2、3、4、5和6 d（T2-10）时测定大鼠后肢机械痛阈和热痛阈.于给药后24h时每组随机取4只大鼠,取脊髓腰膨大标本,采用Western blot法检测磷酸化JNK（p-JNK）的表达,TUNEL法检测脊髓凋亡神经细胞,计算细胞凋亡指数.结果 与Ⅰ组比较,Ⅱ组、Ⅲ组和Ⅳ组机械痛阈和热痛阈、Ⅱ组和Ⅳ组脊髓p-JNK表达差异无统计学意义（P＞0.05）,Ⅴ组T2-4,6-8时机械痛阈、T2-4,7时热痛阈、Ⅵ组T2-6时机械痛阈、T2-5时热痛阈升高,Ⅲ组脊髓p-JNK表达下调,细胞凋亡指数降低,Ⅴ组和Ⅵ组脊髓p-JNK表达上调,细胞凋亡指数升高（P＜0.05）；与Ⅴ组比较,Ⅵ组T2-8时机械痛阈和热痛阈降低,给药后24h时脊髓p-JNK表达下调,细胞凋亡指数降低（P＜0.05）.结论 JNK信号转导通路激活可能通过促进脊髓神经细胞凋亡参与利多卡因诱发大鼠脊髓神经毒性的过程.

英文摘要：

Objective To evaluate the role of C-Jun N-terminal kinase （JNK） signal transduction pathway in spinal neurotoxicity induced by lidocaine in rats.Methods Seventy-two adult male Sprague-Dawley rats,weighing 220-260 g,were randomly divided into 6 groups （n =12 each）：control group （group Ⅰ）,sham operation group （group Ⅱ）,JNK inhibitor group （group Ⅲ）,dimethyl sulfoxide （DMSO） group （group Ⅳ）,lidocaine group （group Ⅴ）,and JNK inhibitor and lidocaine group （group Ⅵ）.Group Ⅰ received no treatment.Intrathecal catheter was placed in the subarachnoid space in group Ⅱ.SP600125 25 μg and DMSO 20 μl were injected intrathecally in Ⅲ and Ⅳ groups,respectively.In group Ⅴ,10% lidocaine 20 μl was intrathecally injected.SP600125 25 μg was injected intrathecally and 30 min later 10% lidocaine 20 μl was injected intrathecally in group Ⅵ.Paw withdrawal threshold to yon Frey filament stimulation （PWT） and paw withdrawal latency to nociceptive thermal stimulation （PWL） were measured before intrathecal catheter was implanted （T0）,before intrathecal administration （T1） and at 4,8 and 12 h and on 1,2,3,4,5 and 6 days after intrathecal administration （T2-10）.At 24 h after intrathecal administration,4 rats were randomly chosen from each group and sacrificed.Their lumbar enlargements were removed for determination of phosphorylated JNK （p-JNK） expression （using Western blot） and neuronal apoptosis （by TUNEL）.The apoptotic index was calculated.Results Compared with group Ⅰ,no significant difference was found in MWT and TWL in Ⅱ,Ⅲ groups and expression of p-JNK in Ⅱ and Ⅳ groups （P 〉 0.05）,MWT at T2-4,6-8 and TWL at T2-4,7 in group Ⅴ and MWT at T2-6 and TWL at T2-5 in group Ⅵ were significantly increased,the expression of p-JNK was down-regulated and the apoptotic index was decreased in group Ⅲ （P 〈 0.05）,and the expression of p-JNK was up-regulated and the apoptotic index was increased in Ⅴ and Ⅵ groups （P 〈 0.