乌司他丁联合葛根素对大鼠急性肺损伤模型Toll样受体4表达的影响

Effects of ulinastatin combined with puerarin on toll-like receptor 4 expression in rats with acute lung injury

目的研究乌司他丁联合葛根素对大鼠急性肺损伤(ALI)模型Toll样受体4(TLR4)表达的影响。方法将50只Wistar大鼠随机分为正常组、模型组、对照组Ⅰ、对照组Ⅱ和实验组,每组10只。腹腔注射5 mg·kg^(-1)大肠埃希菌脂多糖(LPS)建立急性肺损伤大鼠模型,正常组腹腔注射等量生理盐水。分别于建模前24,12 h及建模后12 h,对照组Ⅰ腹腔注射10万U·kg^(-1)乌司他丁,对照组Ⅱ灌胃5 mg·kg^(-1)葛根素,实验组腹腔注射10万U·kg^(-1)乌司他丁+灌胃注射5 mg·kg^(-1)葛根素,模型组和正常组则灌胃等量生理盐水。苏木精-伊红(HE)染色观察急性肺损伤大鼠肺组织形态,评价急性肺损伤大鼠肺水肿程度,用蛋白免疫印迹法检测急性肺损伤大鼠肺组织TLR4蛋白表达。结果正常组、模型组、对照组Ⅰ、对照组Ⅱ和实验组肺组织病理学评分分别为0,(2.95±0.43),(2.51±0.45),(2.41±0.43),(1.80±0.34)分,肺组织湿干重比(W/D)分别为3.96±0.24,5.32±0.34,4.53±0.29,4.46±0.27,4.21±0.25,TLR4蛋白相对表达量分别为1.00,3.01±1.07,1.96±0.85,1.87±0.92,1.54±0.56。模型组大鼠肺组织病理学评分、肺水肿程度及TLR4蛋白含量均显著高于正常组(均P<0.01);对照组Ⅰ、对照组Ⅱ和实验组上述指标均明显低于模型组(P<0.05或P<0.01),其中实验组肺组织病理学评分、肺组织W/D均低于对照组Ⅰ、对照组Ⅱ(均P<0.05),但3组间TLR4蛋白含量差异均无统计学意义(均P>0.05)。结论乌司他丁联合葛根素可更有效地降低急性肺损伤大鼠肺组织损伤及肺水肿程度,可能与降低TLR4蛋白表达有关。

Objective To investigate the effect of ulinastatin combined with puerarin on the expression of toll-like receptor 4（ TLR4） in rats with acute lung injury（ ALI）. Methods Fifty Wister rats were randomly divided into 5 groups： normal group,model group,control group Ⅰ,control group Ⅱ and test group,10 rats in each group. A rat model of acute lung injury was established by intraperitoneal injection of 5 mg·kg^（-1） E. coli lipopolysaccharide（ LPS）. The normal group received intraperitoneal injection of normal saline. At the 24 and 12 h before modeling and 12 h after modeling,1 × 105 U·kg^（-1） ulinastatin was intraperitoneally injected into control group I,and 5 mg·kg^（-1） puerarin was intragastrically injected into control group Ⅱ. Intraperitoneal injection of1 × 105 U·kg^（-1） ulinastatin was given into test group as well as intragastric administration of 5 mg·kg^（-1） puerarin. The model group and normal group were intragastrically injected with equal volume of normal saline. Hematoxylin-eosin（ HE） staining was used to observe the morphology of lung tissue in rats with acute lung injury. The degree of pulmonary edema was evaluated in rats with acute lung injury. The expression of TLR4 protein in lung tissue of rats with acute lung injury was detected by Western blotting. Results The histopathological scores（ score） of normal group,model group,control group Ⅰ,control group Ⅱ and test group were 0,2. 95 ± 0. 43,2. 51 ± 0. 45,2. 41 ± 0. 43,1. 80 ± 0. 34,the wet/dry weight ratio（ W/D） of lung tissue were 3. 96 ± 0. 24,5. 32 ± 0. 34,4. 53 ± 0. 29,4. 46 ± 0. 27,4. 21 ± 0. 25, the relative expression of TLR4 protein were 1. 00,3. 01 ± 1. 07,1. 96 ± 0. 85,1. 87 ± 0. 92,1. 54 ± 0. 56. The histopathological score,pulmonary edema and TLR4 protein content in model group were significantly higher than those in normal group（ all P〈0. 01）,control group Ⅰ,control group Ⅱ and test group were significantly lower than model group（ P〈0. 05 or P〈0. 01）,the histopathological score and W/D of lung tissue in test group were lower than those of control group Ⅰ and control group Ⅱ（ all P〈0. 05）,but there was no significant difference in TLR4 protein content among 3 groups（ all P〈0. 05）.Conclusion Ulinastatin combined with puerarin can reduce the lung injury and pulmonary edema in ALI rats more effectively,which may be related to the decrease of TLR4 protein expression.