Aim: To study the kinetics of tumor necrosis factor alpha (TNF alpha), interleukine-1 (IL-1 beta), and macrophage inflammatory protein-1 alpha (MIP-1 alpha) gene expression in rat lung after i.p. lipopolysaccharides (LPS) and the effect of dexamethasone (Dex) and ibuprofen (Ibu) on the cytokines gene expression.
Methods: The amount of Evans blue in lung was measured by fluorescence method. The mRNA levels of TNF alpha, IL-1 beta, and MIP-1 alpha in rat lung were assessed by slot blot analysis.
Results: The mRNA levels of TNF alpha, IL-1 beta, and MIP-1 alpha in rat lung after i.p. LPS increased in a dose-dependent manner, and peaked at 2, 6, and 12 h, respectively. Both Dex 50 mg.kg-1 and Ibu 90 mg.kg-1 injected at 1 h before i.p. LPS markedly decreased the content of Evans blue in lung at 1 h after i.p. LPS. After Dex or Ibu pretreatment, the peak levels of TNF alpha, IL-1 beta, and MIP-1 alpha mRNA decreased markedly compared with LPS alone.
Conclusion: The gene expression of TNF alpha, IL-1 beta, and MIP-1 alpha in rat lung increased after i.p. LPS. Dex and Ibu prevented LPS-induced lung injury through inhibiting the cytokines gene expression.