动物造模 z-bio 2022-07-01 517

　　Objective: To understand the dynamic changes and regularities of gene expression levels of metallothioneins (MTs) in the development of mouse hepatocellular carcinoma (HCC), and to explore the significance of MTs in the development of HCC.

　　Methods: 125 male C57BL/6J mice aged 5-8 weeks were randomly divided into normal control group and HCC model group. The mice in the model group were given intraperitoneal injection of diethylnitrosamine (100 mg/kg, 50 mg/kg) on the 1st and 2nd week respectively, and ethanol (53%, 5 mL/kg, 5 d/week) until 35 weeks; the normal group was always given the same amount of sterilized tap water by gavage. Mice were sacrificed at the end of experiment 1, 3, 9, 13, 24 and 35, respectively, and liver tissue samples were collected and liver index was calculated. Histopathological HE, Masson and reticular fiber staining were used to detect the occurrence of liver tissue damage and HCC, and enzyme-linked immunosorbent assay was used to detect the activity of malondialdehyde (MDA) in liver tissue homogenate. Real-time fluorescence quantitative PCR was used to analyze the transcription level of MTs. .

　　Results: The mice in the model group had progressive liver lesions. At the end of the 35th week, the liver texture was significantly hardened, and nodules of different sizes were formed on the surface. About 50% of the mice had abnormal mitotic images of liver cells and abnormal liver plate structure. HCC had pathological changes, with significantly increased liver index; increased MDA activity in different time periods; significantly increased MTs mRNA levels in each time period before 13 weeks of the experiment, grade III fibrosis was seen after 24 weeks, and MTs mRNA levels Significantly lower, even lower than normal levels.

　　Conclusion: The level of MTs mRNA in mouse liver tissue changes from a significant increase in the early stage of injury to a low expression change after significant fibrosis, indicating that the down-regulation of MTs expression is related to the occurrence of HCC.