小剂量二乙基亚硝胺诱导大鼠肝纤维化模型的建立

目的 探讨采用小剂量二乙基亚硝胺（DEN）诱发大鼠肝纤维化实验性模型的方法。方法 取Wistar大鼠30只,随机分为模型组和正常组,每组15只。给予模型组DEN溶液10 mg·kg^-1灌胃,1次/d。在10周后,处死动物,取肝组织行病理学检查和细胞超微结构观察。测定血清超氧化物歧化酶（SOD）、丙二醛（MDA）、谷胱甘肽过氧化物酶（GSH-Px）含量。结果 模型组动物血清ALT和AST水平分别为（410.1±93.6） U/L和（399.7±90.9） U/L,显著高于对照组【（56.51±11.2） U/L 和（63.26±10.0）U/L,P<0.001】,模型动物血清SOD、GSH-Px和MDA活性分别为（83.08±22.0) U/mg、（24.65±2.0） U/mg和（9.78±2.0) nmol/mg,与对照组比,均有显著性差异【（178.57±22.8）U/mg、（45.16±2.9）U/mg和（3.76±0.7）U/mg,P<0.01】;模型组动物肝组织肝细胞变性、增生、坏死和假小叶形成,超微结构改变以肝细胞核内异染色质增加、细胞器数量减少、基质密度降低和肝糖元减少表现为主。结论 采用小剂量DEN能成功诱导大鼠肝纤维化模型,造模成功率高,病变稳定。

Establishment of low-dose diethylnitrosamine-induced liver fibrosis model in rats

Objective To establish liver fibrosis model with low-dose diethylnitrosamine（DEN） in rats. Methods Thirty Wistar rats were randomly divided into model group and control group with 15 in each. The rats in the model group were treated with low-dose DEN（10 mg·kg^-1 body weight,orally,once daily） for 10 weeks. After sacrificing,the hematoxylin and eosin staining was performed to determine histopathological alterations and transmission electron microscopy（TEM） was used to observe the changes of ultrastructures in the hepatic cells. The automatic biochemical analyzer was used to measure ALT and AST levels,and biochemical methods was used to determine the content of serum SOD,MDA and GSH-Px. Results The levels of ALT and AST in the model group were（410.08±93.6） U/L and（399.7±90.9） U/L,respectively,significantly higher than those in the control group （56.51±11.2） U/L and（63.26±10.0） U/L,P<0.001];serum contents of SOD,GSH-Px and MDA in the model group were（83.08±22.0） U/mg,（24.65±2.0） U/mg and （9.78±2.0） nmol/mg,respectively,significantly lower than those in the control group（178.57±22.8） U/mg,（45.16±2.9） U/mg and（3.76±0.7） U/mg,P<0.01];the histological alterations of liver cells in the model group were mainly hepatic deforming,proliferation,necrosis and pseudolobule formation and the ultrastructural changes were mainly the increase of heterochromatin in the nucleus,decrease of organelle,matrix density and hepatin. Conclusion Low-dose DEN could successfully induce liver fibrosis and cirrhosis in rats with a high successful rates and stable pathological changes.