右美托咪定对大鼠脊髓缺血再灌注损伤炎性细胞因子TNF-α和IL-8的影响

Effect of Dexmedetomidine on Inflammatory Cytokine TNF-α and IL-8 of Rat Spinal Cord Ischemia Reperfusion Injury

目的探讨右美托咪定(Dex)对脊髓缺血再灌注损伤大鼠脊髓组织及血浆TNF-o和IL-8表达的影响。方法成年雄性Wister大鼠54只,随机分为3组,假手术组、缺血再灌注组、缺血再灌注Dex处理组。Zivin改进法制作脊髓缺血再灌注模型。Dex组于夹闭腹主动脉前30min输注Dex 5μg/(kg·h)至再灌注后30min。同期内Sham组与I/R组输注等容量生理盐水。再灌注后6h,12h和24h用酶联免疫吸附法和Lowry法分别测TNF-α和IL-8含量。结果①I/R组脊髓组织中TNF-α随再灌注时间延长而逐渐增高,各时间点明显高于Dex组(P<0.05)。缺血再灌注24h后血浆TNF-α含量I/R组和Dex组均有增加,但后者明显低于I//R组(P<0.05)。②各时间点脊髓组织I/R组IL-8含量较Sham组明显升高(P<0.05),Dex组于再灌注12h和24h略高于Sham组,但明显低于I/R组(P<0.05)。再灌注12h和24h I//R组血浆IL-8含量明显高于Sham组(P<0.05),而Dex组各时间点均明显低于I//R组(P<0.05)。结论 Dex能够抑制大鼠脊髓缺血再灌注损伤脊髓组织及血浆TNF-α和IL-8的表达,对脊髓缺血再灌注损伤有一定的神经保护作用。

Objective To explore effects of dexmedetomidine（ Dex} on the expression of TNF-α and IL-8 in plasma and mye- loid tissue after spinal cord isehemia/reperfusion in rats. Methods Fifty-four heahhy male Wister rats weighing 200 - 260g were randomly divided into three groups ： Sham operation group （ Sham group, n = 18 ）, ischemia/reperfusion group （ I/R group, n = 18 ） and Dex treatment group（ Dex gronp,n = 18）. The infusion of Dex 5μg/{ kg · h） （ Dex group） or normal saline（ Sham group and I/R group） was given from the time of 30 minutes before occlusion of abdominal artery to 30 minutes after reperfusion. The TNF-α and IL-8 protein content was assessed at 6h, 12h and 24h reperfusion. Results ①TNF-α in the spinal eord tissue In I/R group was significantly higher than that in Dex group at ey- eD time point（P 〈0.05}. 24h after reperfusion,plasnm TNF-α levels in I/R group and Dex group had increased, but the latter was signifi- cantly lower than the 1/R group（ P 〈 0.05）. ②Compared with Sham group,IL-8 level in spinal cord was significantly higher in I/R group, slightly higher at 12h,24h repeffusion in Dex group which was obviously lower than that in I/R group（ P 〈0.05 ）. The plasma IL-8 in I/R group was signifieanlly higher than that in Sham group at 12h,24h repeffusion （P 〈 0.05） ,while the Dex group were significantly lower than I/R group（ P 〈 0.05 ）. Conclusion When the rat spinal cord ischemia-repeffusion injury occurred, Dex can inhibit the expression of TNF-α and IL-8 in spinal cord tissue an（I plasma,and has a effect of neuroprotective.