【摘要】 目的:检测Toll样受体4(TLR4)在四氯化碳诱导的肝硬化大鼠骨髓血窦内皮细胞的表达,为进一步研究肝硬化时骨髓损伤的发生机制提供实验依据。方法:选择Wistar大鼠给予腹腔注射CCl4,一周两次,建立肝硬化大鼠模型。分别于建模8周和12周检测大鼠血浆内毒素的水平,免疫组化检测大鼠骨髓血窦内皮细胞上TLR4的表达情况,RT-PCR测定骨髓组织中TLR4 mRNA的表达,分析TLR4的表达与内毒素血症间的关系。结果:给予CCl48周和12周时,对照组大鼠血浆内毒素水平分别为(0.216±0.024)Eu/ml和(0.133±0.022)Eu/ml,模型组大鼠血浆内毒素水平分别为(0.626±0.021)Eu/ml和(0.725±0.031)Eu/ml,分别较对照组显著升高,差异均有统计学意义(P<0.001);骨髓血窦内皮细胞TLR4蛋白表达及骨髓组织中TLR4 mRNA的表达均显著高于对照组,差异均有统计学意义(P<0.05)。大鼠骨髓TLR4蛋白和mRNA表达与血浆内毒素水平均呈显著正相关(r=0.841,0.803,P均<0.001)。结论:CCl4诱导的肝硬化大鼠骨髓血窦内皮细胞TLR4表达升高,并伴随大鼠内毒素血症的发生,提示肝硬化时肠源性内毒素血症可能参与了骨髓的造血功能的损害和病变。更多还原

【Abstract】 Objective: To investigate the TLR4 expression on bone marrow endothelial cells and serum endotoxin level in rats with liver fibrosis, and provide experimental basis for the research on the mechanisms of bone marrow damage in liver cirrhosis.Methods: Wistar rats were intraperitoneally injected with carbon tetrachloride(CCl4) twice a week for 8 to 12 weeks to induce liver fibrosis. Serum endotoxin level was assayed and TLR4 expression in bone marrow sinusoidal endothelial cells was detected by immunohistochemistry(IHC). The mRNA level of TLR4 in bone marrow was examined by semiquantitative reverse transcriptase-polymerase chain reaction(RT-PCR). Results: The serum endotoxin levels were 0.216±0.024 Eu/ml and 0.133±0.022Eu/ml in rat with liver cirrhosis induced for 8 weeks and 12 weeks, respectively(P<0.001). IHC examination revealed increased expression of TLR4 on bone marrow sinusoidal endothelium of the cirrhotic rats, compared with the control(P<0.01). mRNA levels of TLR4 on bone marrow tissues from cirrhotic rats were also higher than that from the control(P<0.05). The TLR4 protein and mRNA expression in bone marrow tissue were significantly correlated with the serum enodotoxin level(r=0.841, 0.803, both P<0.001).Conclusion: With the development of endotoxemia, TLR4 was upregulated on bone marrow sinusoidal endothelial cells in cirrhotic rats induced by CCl4, which indicated that intestinal endotoxemia might contribute to the bone marrow functional lesions.更多还原