天然蒙脱石对大鼠急性肝衰竭血中内毒素及单核细胞表面Toll样受体4表达的影响

Effects of smecta on endotoxins and Toll-like receptor 4 expression on the surface of monocytes in rat model of fulminate hepatic failure

目的研究大鼠急性肝衰竭时血中内毒素(LPS)及单核细胞表面TLR4表达的变化以及天然蒙脱石(思密达)对其表达的影响。方法腹腔注射半乳糖胺建立大鼠急性肝衰竭模型。50只SD雄性大鼠随机分为空白组(A组)、对照组(B组)、模型组(C组)、思密达预防组(D组)和思密达治疗组(E组)。采用双色荧光染色法检测血中LPS;荧光素标记的抗TLR4/抗CD14对大鼠血液单核细胞表面TLR4及CD14分子进行免疫荧光染色,流式细胞仪检测。结果与A组比较,C组、D组和E组LPS及TLR4表达均显著增高(P<0.01);与C组比较,D组和E组LPS及TLR4表达显著降低(P<0.05);D组与E组相比,D组LPS及TLR4表达较低(P<0.05);B组与A组比较LPS及TLR4差异均无统计学意义(P>0.05)。结论大鼠急性肝衰竭时,血中LPS及TLR4的表达显著上调,用思密达预防和治疗后显著下调,且预防组下调更为显著。

Objective To explore the variability of endotoxins in blood and Toll-like receptor 4 expression on the surface of in rats with fulminate hepatic failure,and observe the effect of smecta on LPS and TLR4 expression. Methods Establishing the fulminate hepatic failure model by intraperitoneal injection of Galaetosamine. Fifty male rats were randonly divided into five groups： group A as blank, group B as control, group C as the fulminate hepatic failure models, group D as prevention by smecta; group E as treatment by smecta. Endotoxin in right ventricle were determined by endotoxin detection kit and blood cells from rats were stained with fluorescent labeling anti-TLR4/anti-CDl4 antibodies. Samples were collected and analyzed for two-color immunofluorescence by flow cytometry. Results The concentrations of LPS and the expression of TLR4 were significantly higher in the group C, D and E compared with group A（P〈0.01 ）, and lower in group D and E compared with group C（P〈0.05）. LPS and TLR4 expression were notably decreased in group D compared with group E（P〈0.05）, and they were not significantly different between group A and B（P〉0.05）. Conclusion The level of LPS and expression of TLR4 are up-regulated in rats with fulminate hepatic failure, and can be down-regulated by smeeta. Furthermore, the preventive effect is more satisfactory than therapeutic effect.