TAA致慢性肝病内毒素血症大鼠清道夫受体、CD14表达变化

The Expression of Scavenger Receptor and CD14 in Chronic Liver Injury Rats with Endotoxemia Induced by TAA

目的:观察清道夫受体(SR)和脂多糖受体CD14在TAA介导的慢性肝病内毒素血症大鼠肝组织中的表达。方法:通过大鼠持续灌胃给小剂量(12mg/kg.d)TAA建立大鼠肝损伤内毒素血症模型,HE染色光镜观察肝脏病理变化;改良赖氏法检测大鼠血清ALT、AST;改良过氯酸法测定血清内毒素含量;酶联免疫法检测大鼠血清CD4+和CD8+;免疫组化染色方法观察大鼠肝组织清道夫受体和CD14的表达。结果:TAA诱导后,大鼠肝脏出现片状坏死并可见灶性炎症;血浆ALT、AST及内毒素水平显著升高(P<0.05或P<0.01);血清CD4+、CD8+T细胞明显降低(P<0.01);肝组织CD14表达上调,清道夫受体表达下调,和正常大鼠相比,差异显著(P<0.05)。结论:肝组织SR表达下降和CD14表达增强可能是TAA介导慢性肝病内毒素血症的重要机制。

Objective： To investigate the expression of scavenger receptor and lipopolysaccharide （LPS） receptor CD14 in chronic liver injury rats with endotoxemia induced by TAA. Methods： Continuously oral administrating low-dose （12mg/kg.d） TAA to construct liver injury with endotoxemia model in rats. To observe the pathological damage of liver through HE staining, the levels ofALT, AST in blood serum were detected with modified Reit＇s method, the endotoxin in blood serum were measured by modified perchloric acid method and ELISA was used to detect the CD4＋ and CD8＋ in blood serum .The expression of scavenger receptor and CD14 in liver were observed by immunohistochemical staining and then analyzed by imaged analysis system. Results：After ten-week attacting by low-dose TAA （12mg/kg .d）, patchy necrosis and focus inflammation appeared in rats liver. The content of ALT, AST and endotoxin in blood serum of model significantly increased （P〈0.05 or P〈0.01 ）, while CD4＋, CD8＋ in serum decreased markedly （P〈0.01）. Compared with normal group, the expression of CD14 in liver of model group obviously increased, while the expression of scavenger receptor was down-regulated （P〈0.05）. Conclusions： It may be the important mechanism of chronic liver injury rats with endotoxemia induced by TAA that the lower expression of scavenger receptor and the higher expression of CD14 in liver.