Tat-LK15运载NR2B siRNA治疗慢性炎性疼痛的效果

目的 探讨大鼠鞘内注射细胞穿透肽Tat-LK15介导NR2B siRNA治疗大鼠慢性炎性疼痛的可行性.方法 健康雄性SD大鼠72只,6周龄,体质量180~200 g,采用随机数字表法分为4组(n=18):空白对照组(C组)、慢性炎性痛模型组(CFA组)、Tat-LK15/NR2B siRNA组(siTat-LK15组)和Tat-LK15/阴性对照siRNA组(ncTat-LK15组).除C组不给予任何处理外,其余大鼠右后趾皮下注射完全弗氏佐剂(CFA)制作慢性炎性痛模型.CFA组、siTat-LK15组及ncTat-LK15组于模型制备后第1、3、5天分别鞘内注射生理盐水、Tat-LK15/NR2B siRNA及Tat-LK15/阴性对照siRNA 10μL.每组取12只大鼠于造模前1 d及鞘内注射后3、7、14、21 d时测定机械缩足反应阈(PWMT)和热缩足反应潜伏期(PWTL).每组取6只大鼠于鞘内注射后7 d处死后取脊髓,检测鞘内注射对大鼠脊髓NR2B蛋白表达的影响.结果 鞘内注射后7 d,siTat-LK15组大鼠脊髓NR2B蛋白表达下调.鞘内注射后3、7、14及21 d,siTat-LK15组PWMT与PWTL与CFA组相比明显升高,差异有统计学意义(P<0.01),而ncTat-LK15组PWMT与PWTL较CFA组相比差异无统计学意义(P>0.05).结论 鞘内注射Tat-LK15/NR2B siRNA可有效减轻CFA所致大鼠慢性炎性疼痛.

The effects of NR2B siRNA carring vector Tat-LK15 on chronic pain

Objective To discuss the effects of intrathecal injection of TAT -LK15/NR2B siRNA on chronic pain relieving in vivo.Methods Adult male SD rats were randomly divided into 4 groups, Group C (control group, no treatment), Group CFA (inflammatory pain induced by freund's adjuvant complete and intrathecal injection of saline ) , Group siTat-LK15 (inflammatory pain model and intrathecal injection of Tat -LK15/NR2B siRNA) and Group ncTat-LK15 (inflammatory pain model and intrathecal injection of Tat -LK15/scrambled siRNA).The changes of NR2B ex-pression were detected using western -blot in SCDH of chronic inflammatory pain rats following intrathecal injection .Pain control efficacy was evaluated by 50% mechanical withdrawal threshold ( PWMT ) and thermal withdrawal latency (PWTL).Results NR2B protein expression was efficiently inhibited by intrathecal injection of Tat -LK15/NR2B siR-NA complexes compared with CFA group ( P<0.01 ) , while complexes injection of TAT -LK15 /scrambled siRNA did not show this inhibitory effect .Moreover, injection of Tat -LK15/NR2B siRNA complexes significantly increased PWMT and PWTL in chronic inflammatory rats compared with CFA group ( P<0.01) .Conclusion TAT-LK15 can efficiently deliver siRNA targeting NR2B in vivo and relieve chronic inflammatory pain .