2Hz电针对SNI诱导神经病理性疼痛大鼠脊髓IRF8和mTOR的作用

Effect of 2Hz electroacupuncture on IRF8 and mTOR expression in the spinal cord of SNI-induced neuropathic pain rats

目的:探讨2Hz电针(Electroacupuncture,EA)治疗神经病理性疼痛的脊髓机制是否与抑制IRF8和mTOR的表达有关。方法:雄性SD大鼠24只,随机分为6组:Sham组、SNI组、SNI+Mock EA组、SNI+EA组、SNI+EA+BDNF组和SNI+EA+PBS组。SNI+EA组、SNI+EA+BDNF组和SNI+EA+PBS组在SNI术后1天,给予大鼠双侧的足三里和三阴交穴位进行电针治疗,隔日电针,持续14天。在电针后的第12、13天分别鞘内注射给予BDNF或PBS。在第14天取大鼠L4~L6脊髓,采用qPCR技术检测IRF8和mTOR的mRNA表达水平。结果:与Sham组相比,SNI大鼠脊髓IRF8和mTOR的mRNA表达水平显著升高(P<0.05,P<0.01);与SNI组相比,SNI+EA组大鼠脊髓IRF8和mTOR的mRNA表达明显下调(P<0.05)。而且在外源性给予BDNF后可翻转2Hz电针的作用,致使大鼠脊髓IRF8和mTOR的mRNA表达水平与电针组相比显著上调(P<0.05)。结论:2Hz电针有可能通过下调SNI大鼠IRF8和mTOR的表达来抑制BDNF诱导的中枢敏化,进而缓解神经病理性疼痛。

Objective:To investigate whether the spinal mechanism of 2Hz electroacupuncture(EA)in the treatment of neuropathic pain is related to the inhibition of IRF8 and mTOR mRNA expression.To investigate whether 2Hz electroacupuncture(EA)treatment of neuropathic pain in the spinal cord is related to the expression of IRF8 and mTOR.Methods:24 male SD rats were randomly divided into 6 groups:Sham,SNI,SNI+Mock EA,SNI+EA,SNI+EA+BDNF,and SNI+EA+PBS group.Rats were treated with 2Hz EA stimulus in acupoints of Zusanli and Sanyinjiao bilaterally once every two days for 14 days.After 2Hz EA treatment to SNI rats,intrathecal injection of BDNF or PBS to SNI rats on the 12th and 13th days of EA stimulus.The spinal cord of L4-L6 segments from rats were harvested on day 14 following SNI.The levels of IRF8 and mTOR mRNA expression were detected by qPCR.Results:In comparison to the sham group,SNI obviously induced the elevation of IRF8 and mTOR mRNA expression in the spinal cord(P<0.05,P<0.01).However,administration of 2Hz EA to SNI rats significantly down-regulated the mRNA expression of IRF8 and mTOR in the spinal cord compared to the SNI group(P<0.05).Meanwhile,intrathecal injection of exogenous BDNF could markedly reversed the down regulation of IRF8 and mTOR mRNA expression induced by 2Hz EA in the spinal cord(P<0.05).Conclusions:This study suggested that 2Hz EA may suppress BDNF induced central sensitization by reducing IRF8 and mTOR levels in the spinal cord of SNI rats,thereby alleviates neuropathic pain.