Biochemical components of bronchoalveolar lavage in early experimental asbestosis of the sheep: phospholipase A2 activity, prostaglandin E2 and proteins.

Biochemical analyses of bronchoalveolar lavage (BAL) supernatants of sheep treated with weekly intratracheal instillations (for 6 months) of saline, 2 mg, or 128 mg of asbestos (chrysotile B; UICC) were performed. Our results showed that proteins (either total or its various components) and phospholipase A2 activity were unchanged in the low exposure group as compared to controls. However, in the high exposure group, with histopathological evidence of early asbestosis, there were significant increases in total proteins, albumin, alpha 2-globulin, beta- and gamma-globulins as well as phospholipase A2 activity of BAL fluid. Prostaglandin E2 activity was significantly increased in both low and high dose groups. These changes in protein and lipid components of BAL following asbestos exposure constitute early indices of lung inflammatory reactions which may contribute to the development of asbestosis.