姜黄素对大鼠神经病理性痛的影响

目的 探讨姜黄素对大鼠神经病理性痛的影响.方法 健康雄性SD大鼠108只,体重220～250 g,随机分为6组(n=18):对照组(C组)、假手术组(S组)、慢性压迫性损伤组(CCI组)和不同剂量姜黄素组(Cur1组、Cur2组和Cur3组).C组腹腔注射二甲基亚砜4 ml·kg-1·d-1,持续14 d;S组只分离坐骨神经,然后腹腔注射二甲基亚砜4 ml·kg-1·d-1,持续至术后14 d;CCI组术后腹腔注射二甲基亚砜4 ml·kg-1·d-1,持续至术后14 d;Cur1组、Cur2组或Cur3组术后分别腹腔注射姜黄素30、100、300 mg·kg-1·d-1,持续至术后14 d,姜黄素以二甲基亚砜溶解.于术前2 d和术后1、3、5、7、10、14d时测定热缩足反应潜伏期(TWL)和机械缩足反应阚值(MWT).各组于术后3、7、14 d时各处死6只大鼠,免疫组化法测定脊髓背角和背根神经节中磷酸化c-jun氨基末端蛋白激酶(p-JNK)和c-jun的表达.结果 与CCI组比较,Cur1组和Cur2组术后MWT升高,背根神经节和脊髓背角p-JNK和c-jun表达下调,Cur2组术后TWL升高(P<0.05);与Cur1组比较,Cur2组术后TWL升高,背根神经节和脊髓背角p-JNK和c-jun表达均下调(P<0.05),MWT差异无统计学意义(P0.05).结论 姜黄素30、100mg/kg可减轻大鼠神经病理性痛,100 mg/kg效果更明显,其机制可能与抑制脊髓背角和背根神经节p-JNK和c-jun表达上调有关.

Effect of curcumin on neuropathic pain in rats

Objective To investigate the effect of curcumin on neurepathic pain in rats. Methods One hundred and eight male SD rats weighing 220-250 g were randomly divided into 6 groups (n=18 each): Ⅰ control group (C);Ⅱ sham operation group (S);Ⅲ chronic constrictive injury group (CCI) and Ⅳ,Ⅴ,Ⅵ 3 curcumin treatment groups (Cur<1-3). CCI was produced by placing 3-4 ligatures with 4-0 chromic catgut on right sciatic nerve at 1 mm intervals. Curcumin 30, 100 and 300 mg/kg were given intraperitoneally (IP) every day for 14 days after operation in group Cur1-3. Curcumin was dissolved in DMSO, of which 4 ml/kg was given IP every day for 14 days in group C, S and CCI. Thermal paw-withdrawal latency (TWL) and mechanical paw-withdrawal threshold (MWT) were measured at day 2 before operation and day 1, 3, 5, 7, 10 and 14 after operation. The animals were deeply anesthetized and decapitated at day 3, 7, 14 after operation. The lumbar segment (L4,5) of the spinal cord and dorsal root ganglions (DRGs) were removed for determination of p-JNK and c-jun expression by immuno-histochemistry. Results Curcumin of 30,100 mg/kg significantly increased the MWT and TWL as compared with CCI group. The expression of p-JNK and c-jun in the spinal cord and DRGs was significantly increased in CCI group. Curcumin of 30,100 mg/kg significantly decreased the expression of p-JNK and e-jun in the spinal cord and DRGs as compared with CCI group. Conclusion Curcumin of 30,100 mg/kg can relieve neurepathic pain by inhibiting the up-regulation of p-JNK and c-jun expression in the spinal cord and DRGs.