Nrf2/ARE通路介导右美托咪定减轻肢体缺血/再灌注损伤中的作用  

Nrf2/ARE pathway mediates the reducing effect of Dexmedetomidine on ischemia/reperfusion injury in skeletal muscle

作　　者：袁培根[1] 薛彬彬[1] 林碧[1] 赵喜越[1] 周森[1] 胡一[1] 包财盈 林丽娜[1] 

机构地区：[1]温州医科大学附属第一医院,浙江温州325000

出　　处：《中国应用生理学杂志》2016年第3期250-254,I0005,共6页Chinese Journal of Applied Physiology

基　　金：温州市科技计划项目(Y20140561)

摘　　要：目的:观察Nrf2/ARE通路在右美托咪定(DEX)预处理减轻大鼠肢体缺血/再灌注损伤中的作用。方法:28只成年雄性SD大鼠随机分为4组(n=7):假手术组(Sham组)、缺血再灌注组(I/R组)、I/R+右美托咪定预处理组(DEX组)、I/R+DEX+阿替美唑组(Atip组)。Atip组在麻醉后腹腔一次性给予Atip(250μg/kg)和DEX(25μg/kg),Sham组和I/R组在麻醉后腹腔给予相应体积生理盐水,DEX组给予相应体积DEX和生理盐水,30min后单侧股部切口,无创动脉夹夹闭股动脉,侧支循环用橡皮筋以恒定张力结扎,缺血3 h后去除动脉夹及橡皮筋,开放2 h后,取大鼠血清测乳酸脱氢酶(LDH)、肌酸激酶(CK);取部分腓肠肌,测量丙二醛(MDA)、超氧化物歧化酶(SOD)以及Western blot检测胞核核因子E2相关因子2(Nrf2)、胞浆HO-1蛋白;免疫组化检测胞核Nrf2、胞浆HO-1蛋白和光镜观察骨骼肌形态;同时切取少量腓肠肌进行湿干比检测。结果:与Sham组相比,I/R组湿干比、MDA、LDH、CK、Nrf2、HO-1蛋白表达明显升高(P<0.05),SOD活性显著降低(P<0.05);与I/R组相比,DEX组湿干比、MDA、LDH、CK明显降低(P<0.05),SOD、Nrf2、HO-1蛋白表达显著增多(P<0.05);与DEX组相比,Atip恰能扭转DEX的这种作用,Atip组各指标与DEX组有显著差异(P<0.05)。结论:Nrf2蛋白存在于大鼠的骨骼肌中并且DEX可以通过α2受体上调核内Nrf2水平,使Nrf2下游的HO-1保护蛋白增多,起到抗氧化的作用。Objective： To explore the role of Nrf2 /ARE pathway in skeletal muscle ischemia/reperfusion（I/R）injury preconditioning by dexmedetomidine（ DEX）. Methods： Twenty-eight SD rats were randomly divided into sham-operated（ Sham group） 、I / R group、I / R ＋ DEX（ DEX group） and I / R ＋ DEX ＋ Atipamezole（ Atip group）. In the Atip group,Atip（250 μg / kg） and DEX（25 μg /kg） were injected together after anesthesia; In the Sham and I / R groups,the homologous saline was also injected at the same time; In the DEX group,the homologous DEX and saline were coinjected. After 30 minutes,the hind limb ischemia was induced by clamping the common femoral artery and ligaturing collateral circulation. After 3 h of ischemia,the clamp and tourniquet were removed and the rats underwent 2 h of reperfusion. We measured plasma concentrations of lactate dehydrogenase（ LDH） and creatine kinase（ CK）. The gastrocnemius muscle was harvested and immediately stored at-80℃ for the assessment of malondialdehyde（ MDA） 、superoxide dismutase（SOD） and Nrf2/HO-1 protein detected by Western blot. The other section muscle was stored in triformol for immunohistochemical and HE staining. The wet / dry was also immediately detecting. Results： The levels of wet / dry、MDA、LDH、CK、Nrf2 and HO-1 were higher（P 0. 05） while the level of SOD was lower（P 0. 05） in the I/R group than those in sham group. The levels of wet/dry、MDA、LDH、CK were significantly lower（ P 0. 05） yet the levels of SOD and Nrf2 / HO-1 were significantly higher（ P 0. 05） in DEX group than those in I / R group. However,Atip reversed the effect of DEX in Atip group,each of indicators had significant changes compared with those in the DEX group（ P 0. 05）. Conclusion： Nrf2 protein was expressed in skeletal muscle of rat and DEX could promote its level in nucleus by α-adrenergic receptor. The down-stream products of Nrf2 have the effect of antioxidant.

关 键 词：缺血/再灌注损伤 氧化应激 核因子E2相关因子2 右美托咪定 大鼠 

分 类 号：R364[医药卫生—病理学]