Experimental study of dexamethasone intervention on variation of serum cytokines TNF-α,IL-8 and IL-10 in rabbits with oleic acid ARDS

Objective: To observe the effects and mechanism of dexamethasone intervention on variations of tumor necrosis factor-α(TNF-α)、interleukin-8(IL-8) and IL-10 in serum of rabbits with acute respiratory distress syndrome(ARDS) induced by oleic acid at different time points.Methods:Totally 40 rabbits were randomly divided into normal control group(n=8),ARDS group(n=8) and dexamethasone-treated group(n=24).Animal model of ARDS was established by intravenous injection of oleic acid to rabbits' veins through ear margin.Dexamethasone-treated group was subdivided into three groups(n=8)by injecting dexamethasone at different time points(instantly,1,2 h).Levels of TNF-α,IL-8 and IL-10 in serum were measured using radioimmunoassay and enzyme linked immunosorbeng assay(ELISA).Results:Levels of TNF-α and IL-8 in serum were significantly higher in ARDS group than in normal control group(P0.01).Level of IL-10 in serum was significantly lower in ARDS group than in normal control group(P0.01).After dexamethasone treatment,levels of TNF-α and IL-8 in serum were lowered while level of IL-10 in serum was increased.Levels of TNF-α,IL-8 and IL-10 in serum were statistically different between dexamethasone-treated group and ARDS group(P0.01).Different variations of TNF-α,IL-8 and IL-10 levels in serum were observed when dexamethasone was given at different time points. Conclusions:TNF-α,IL-8 and IL-10 may play an important role in the inflammatory process of oleic acid ARDS in rabbits.Dexamethasone may relieve lung injuries by intervening the secretion process of TNF-α,IL-8 and IL-10.At the same time,the possible relationships may exist between the progression of inflammation and the intervention time of dexamethasone.