三氯乙烯对肝细胞一氧化氮和诱导型一氧化氮合酶表达水平的影响

Nitric Oxide Synthesis and iNOS Expression in L02 Hepatocytes Treated with Trichloroethylene

[目的]研究三氯乙烯(TCE)染毒对L-02肝细胞一氧化氮(NO)合成和诱导型一氧化氮合酶(iNOS)表达水平的影响。[方法]用TCE不同浓度(0、0.125、0.25、0.5、1.0、2.0mmol/L)和1.0mmol/L TCE不同染毒时间(0、1、2、6、12、24h)染毒肝细胞。按试剂盒说明检测细胞培养液中NO浓度;提取肝细胞RNA,用荧光定量聚合酶链式反应(PCR)检测肝细胞iNOS mRNA相对表达量。用全自动生化分析仪测定TCE染毒肝细胞后培养液中丙氨酸转氨酶(ALT)、天冬氨酸转氨酶(AST)和乳酸脱氢酶(LDH)活性。[结果]不同浓度TCE染毒肝细胞24h后,各染毒组和对照组比较,NO和iNOS mRNA表达水平均明显升高;用同一浓度TCE(1.0mmol/L)染毒不同时间,≥2h染毒时间引起NO合成和iNOS mRNA表达水平升高。TCE各剂量组染毒后ALT、AST和LDH高于对照组。[结论]TCE染毒肝细胞可诱导肝细胞iNOS mRNA表达水平升高和NO合成增加,并对肝细胞有一定的损伤作用,提示TCE的肝细胞损害作用可能与NO产生有关。

[Objective]To study the effects of trichloroethylene （ TCE ） on nitric oxide synthesis and the expression of inducible nitric oxide synthase （iNOS ）in hepatocytes treated with TCE. [ Methods ] L02 hepatocytes were treated with different doses of TCE（ 0, 0.125, 0.25, 0.5, 1.0, 2.0mmol/L ） and various period（ 0, 1, 2, 6, 12, 24h ）of TCE（1.0retool/L）. Nitric oxide was determined in the culture supematants according to the kit instruction, and the relative expression of iNOS mRNA was detected with real time-PCR. Additionally, the levels of ALT, AST and LDH were determined with automatic biochemistry analyzer. [ Results ] The levels of NO increased in all groups treated with TCE for 24h when compared with control, the relative expression of iNOS mRNA also increased after TCE treatment. In addition, NO levels and iNOS mRNA expression elevated when cells were treated with TCE for 2 h or longer. The levels of ALT, AST and LDH in the TCE-treated group were higher than that in the control. [ Conclusion ] TCE could induce the expression of iNOS mRNA as well as the production of NO in hepatocytes, furthermore, cytotoxicity was observed in hepalocytes after TCE treatment. These findings indicated the cytotoxicity could be associated with NO production in hepatocytes when treated by TCE.