ABSTRACT
This chapter focuses on a different aspect of NO2 injury to the lung and discuss the effect of NO2 from the vantage point of the experimental athologist. It examines certain aspects of the structure and function of the isolated lungs and airways at the termination of the exposure. When the airways of hamsters chronically exposed to NO2 are studied, a number of unusual degenerative and proliferative lesions are observed in the epithelial lining of the airways. Exposure to NO2 in higher concentrations for periods of 12 months demonstrated similar results; namely, no significant changes in compliance, total pulmonary resistance, or UAR in hamsters. The injury, erosion, and repair of the surface cilia are in contrast to a bizarre observation within the deeper layer of the epithelial cells. In this locus, after several months of NO2 exposure, intraepithelial cilia appear. Within 5 months after the initiation of NO2 exposure, nodules and papillomata develop in the bronchial and bronchiolar epithelium.
