Figure 6.

Morphological changes. Representative figures for control animals (A, HE staining; C, Alcian blue) and animals exposed to 80 ppm SO2 for 20 days (B, HE staining; D, Alcian blue) illustrate airway remodeling with organized, histologically normal epithelium in the control group and structurally altered epithelium after 20 days of exposure. Epithelial cells displayed an increased height and a loss of ciliae. Alcian blue staining (C, D) demonstrates an increase of mucus positive cells within the epithelium and a loss of ciliae. Original magnification ×400.