Morphological Alterations to the Bronchial Mucosa in High-Dosage Long-Term Exposure to Sulfur Dioxide

Publisher Website
Google Scholar
Abstract
Light and electron microscopic studies were carried out on chronic bronchitis in the rat, produced by high dosage, long term exposure to SO2. Particular attention was given to the advanced stages of the disease. Inflammatory intramural infiltration and fibrosis developed in regions of the bronchial tree near the hilus and in peripheral sections. The highly differentiated cells of the bronchial epithelium perish at the same time. After a loss of the goblet and ciliate cells, extensive epithelial metaplasias with dysplasias develop in central regions of the bronchus. Bronchiolitis obliterans develops in peripheral regions of the bronchus. In bronchiolar epithelium Clara cells, which play a crucial role in the bronchial secretion maintenance in advanced stages of the disease, are preserved.