Changes of IL-18, TNF-α and IFN-γ levels in rats with experimental cirrhosis and their significance / 西安交通大学学报(医学版)

ABSTRACT

Objective To investigate the changes of interleukin-18 (IL-18), tumor necrosis factor-α(TNF-α) and interferon-γ (IFN-γ) levels of liver cirrhosis induced by the composite factors of carbon tetrachloride (CCl_4) in SD rats and their significance. Methods Totally 80 male SD rats of clean class were randomly divided into normal control group (20 rats) and model groups, the latter of which were further divided into three groups according to the length of administration time, namely, 2-week group (2 wk group), 4-week group (4 wk group) and 6-week group (6 wk group), with 20 rats in each. Six rats were killed after 2 wk, 4 wk and 6 wk administration time, respectively. The rat serum levels of IL-18, TNF-α and IFN-γ and the hepatic homogenate supernatant of IL-18 were detected by ELISA; pathological changes of liver tissues were observed by HE staining. Results ① Pathological observation revealed that in the model groups hepatic cells degenerated and swelled at week 2 while large amounts of fibrosis and pseudolobules of some liver tissues occurred at week 6. ② The serum levels of IL-18, TNF-α and IFN-γ were gradually increased with the modeling time, and they were significantly higher in 6-week group than in normal control group (P<0.01). ③ The levels of hepatic homogenate supernatant of IL-18 in the model groups were elevated with liver damage, and they were significantly higher in 6-week group than in normal control group (P<0.01). Conclusion During the formation of liver cirrhosis induced by composite factors of CCl_4 in rats, IL-18, TNF-α and IFN-γ levels gradually increase, suggesting that the three cytokines play a certain role during the occurrence of liver cirrhosis in rats.