Preliminary studies on the fibrogenic effects of silicotic pulmonary lavage in normal rat lung

Abstract

The biological activity of silica free broncho‐pulmonary lavage (BPL) obtained from silicotic rats was determined by injecting intratracheally into fresh group of rats or by exposure to a suspension of sheep erythrocytes. The BPL obtained at 8, 16 and 45 days after silica inoculation, revealed no hemolytic action on sheep red blood corpuscles. However, when injected intratracheally into fresh rats, the BPL caused mild exudative and cellular changes into the alveolar spaces at early periods. At later periods, marked interstitial thickening due to infiltration by mononuclear cells, foamy macrophages and fibroblasts resulted. The 16 day old silicotic BPL involved larger areas of pulmonary parenchyma and caused more fibroblastic proliferation as compared to BPL obtained at other periods.

Key words:

• Bronchoalveolar lavage
• silicosis
• fibrosis
• quartz