摘要
目的 探讨Toll样受体是否参与小鼠肝脏缺血再灌注损伤及其机制。方法 用Toll样受体缺损小鼠(C3H/Hej,Hej组)和野生型(C3H/Heouj,Heouj组)小鼠复制部分肝脏缺血再灌注损伤模型,于缺血45min,再灌注1h和3h处死动物,检测血清天门冬氨酸氨基转移酶(AST)和血清肿瘤坏死因子α(TNFα)的含量;并以northern blot及髓过氧化物酶(MPO)试验分别检测缺血肝组织TNFα mRNA的表达和MPO的含量。结果(1)再灌注1、3h,与假手术组相比,小鼠血浆AST明显升高,但Hej组明显低于Heouj组(661.83U/L±106.09U/L和1215.5U/L±174.03U/L,t=-6.65,P<0.01;1145.17U/L±132.43U/L和2958.17U/L±186.81U/L,t=-5.57,P<0.01);(2)再灌注3h时,与假手术组相比,Hej组和Heouj组小鼠血清TNFα浓度明显升高,且前者明显低于后者(152.39pg/ml±43.3pg/ml和249.12pg/ml±51.89pg/ml,t=-3.13,P<0.05);(3)再灌注1h,除假手术组外,Hej组和Heouj组小鼠缺血肝组织内可见TNFα mRNA的表达,但前者的表达水平明显低于后者,杂交带密度分析显示两者之间差异有显著性(80.3±28.8与189.4±24.6,t=-3.25,P<0.05);(4)再灌注3h,与假手术组相比,Hej组和Heouj组小鼠缺血肝组织内MPO含量明显升高,且前者含量明显低于后者(0.059±0.004和0.173±0.025,F=33.49,P<0.01)。结?
Objective To explore the role of TLR4 in the mechanism of hepatic ischemia/reperfusion (I/R) injury in mice. Methods Wild-type (C3H/Heouj) mice and TLR4 deficient mice (C3H/Hej) were used to prepare the models of liver I/R injury. Partial hepatic ischemia was produced by inflow causing occlusion in the median and left lobes for 45 minutes. Blood was drawn to kill the mice at 1 hours and 3 hours after reperfusion. The blood was used to analyze aspartate aminotransferase (AST) and tumor necrosis factor-alpha (TNFa). TNF-a mRNA expression and myeloperoxidase (MPO) level in ischemic lobes was examined by northern blot and myeloperoxidase assay, respectively. Results AST levels were significantly lower in TLR4 deficient mice, compared with those in wild-type mice at both time points (661.83 U/ L ± 106.09 U/ L vs 1 215.5 U/ L ± 174.03 U/ L, t = -6.65, P < 0.01; 1 145.17 U/ L ± 132.42 U/L vs 2 958.17 U/ L ± 186.81 U/ L, t = -5.57, P<0.01). Serum TNF-a level was lower in TLR4 deficient mice at 3 hours after reperfusion compared with that in wild-type mice (152.39 pg/ml ± 43.3 pg/ml vs 249.12 pg/ml ± 51.89 pg/ml, t = -3.13, P < 0.05). This difference appeared to be mediated at the gene level, since TNF- a mRNA expression had decreased in TLR4 deficient mice at 1 hours after reperfusion, compared with that in wild type mice (80.3 ± 28.8 vs 189.4 ± 24.6, t = -3.25, P < 0.05). MPO level in ischemic lobes in TLR4 deficient mice at 3 hours after reperfusion was significantly lower than that in wild type mice (F = 33.49, P < 0.01). Conclusions I/R hepatic injury in TLR4 deficient mice is less than that in wild-type mice. TNF- a expression down-regulated at the mRNA level appears critical. These suggest that TLR4 be involved in the mechanism of hepatic ischemia/reperfusion injury in mice.
出处
《中华肝脏病杂志》
CAS
CSCD
2003年第7期424-426,共3页
Chinese Journal of Hepatology
基金
教育部留学基金
