The effects of interleukin-10 and dexamethasone on expression of TNF-? mRNA, IL-1? mRNA, IL-1ra mRNA in acute lung injury in rats / 解放军医学杂志

ABSTRACT

Objective To evaluate the effects of interleukin-10 and dexamethasone on expression of TNF-? mRNA, IL-1? mRNA, and IL-1ra mRNA in acute lung injury (ALI). Methods A rat model of ALI was reproduced by intratracheal instillation of endotoxin (LPS) with a dose of 10mg/kg. 72 male S-D rats were randomly divided into control group, LPS group, LPS+IL-10 group, and LPS+Dex group, 18 rats in each group (6 rats at 2h, 6h, and 24h respectively). RT-PCR method was used to determine the expression of TNF-? mRNA, IL-1? mRNA, and IL-1ra mRNA in lung tissue. Results In LPS group TNF-? mRNA expression peaked at 2h, then decreased sharply; IL-1? mRNA expression increased markedly at 2h, peaked at 6h, then decreased; IL-1ra mRNA expression increased and peaked at 6h, and remained higher than control group at 24h. Both IL-10 and Dex inhibited TNF-? mRNA and IL-1? mRNA expression, but with no effect on IL-1ra mRNA expression. Pathological examination revealed that IL-10 or Dex attenuated injury to lung parenchyma. Conclusions The up-regulation of expression of both TNF-? mRNA and IL-1? mRNA was much earlier than that of the expression of IL-1ra mRNA, suggesting that there was an imbalance of inflammatory and anti-inflammatory mediators in the early phase of ALI. Both IL-10 and Dex could inhibit the expression of inflammatory mediators and exert no effect on the expression of anti-inflammatory mediators, thus contributing a balance effect between them and relieving ALI in rats.