Lung collagen types are altered in rats chronically exposed to ozone

A new method has been developed for the quantitative determination of collagen types I and III in the lung, using CNBr digestion to solubilize peptides from these collagens, followed by quantification by an enzyme-linked immunosorbent assay (ELISA) using a polyclonal goat antibody against the α1(1)-C83 peptide. Collagen type ratios were determined for lung tissue from normal rats and from animals that had been chronically exposed to ozone for durations of exposure of either 90 days or 20 mo. Increases in the relative ratio of type I:III collagen were demonstrable in the lungs of rats exposed for 5 days/wk, 6 h/day, to ozone for 20 too, even at concentrations of ozone as low as 0.12 ppm.