AIM　To study the effects of dexamethasone on expressing monocyte chemoattractant protein-1(MCP-1 ) mRNA in the rats with pulmonary fibrosis, elaborate the molecular mechanism of dexamethasone (Dxs) in pulmonary fibrosis therapy. METHODS　The model of pulmonary fibrosis was established by instilling bleomycin intratracheally. After treating with Dxsip, the levels of MCP-1 mRNA were determined by RT-PCR. The histological changes were observed and the numbers of inflammatory cells were counted in optical microscopy field. RESULTS　The accumulation of inflammatory cells decreased markedly, and the symptom of pulmonary fibrosis was alleviated. Furthermore, Dxs evidently inhibited the expression of MCP-1 mRNA in lung tissues with pulmonary fibrosis. CONCLUSION　The molecular mechanism of Dxs in pulmonary fibrosis therapy was associated with inhibiting the expression of MCP-1 mRNA.

AIM To study the effects of dexamethasone on expressing monocyte chemoattractant protein 1(MCP 1 ) mRNA in the rats with pulmonary fibrosis, elaborate the molecular mechanism of dexamethasone (Dxs) in pulmonary fibrosis therapy. METHODS The model of pulmonary fibrosis was established by instilling bleomycin intratracheally. After treating with Dxs ip , the levels of MCP 1 mRNA were determined by RT PCR. The histological changes were observed and the numbers of inflammatory cells were counted in optical microscopy field. RESULTS The accumulation of inflammatory cells decreased markedly, and the symptom of pulmonary fibrosis was alleviated. Furthermore, Dxs evidently inhibited the expression of MCP 1 mRNA in lung tissues with pulmonary fibrosis. CONCLUSION The molecular mechanism of Dxs in pulmonary fibrosis therapy was associated with inhibiting the expression of MCP 1 mRNA.