Quantitative Histology and Cytochrome P-450 Immunocytochemistry of the Lung Parenchyma Following 6 Months of Exposure of Strain A/J Mice to Cigarette Sidestream Smoke

Abstract

AbstractMale strain A/J mice were exposed for 6 h/day, 5 days/wk to aged and diluted cigarette sidestream smoke (ADSS) at a chamber concentration of 4 mg/m3 of total suspended particulate matter (TSP). After 6 mo, the lungs were examined for altered expression of cytochrome P-450 isozymes and for differences in total alveolar tissue volume or surface area, as well as changes in the numbers of epithelial type II cells and alveolar macrophages. Morphologic measurements showed no statistically significant differences for the air, alveolar tissue, or capillary volumes of the lungs or changes in the total number of epithelial type II cells or alveolar macrophages. In contrast, cytochrome P-4501A1 was elevated in the lungs of ADSS-exposed animals and localized in capillary endothelial cells. CYP2B1 was present in airway epithelial cells as well as in epithelial cells throughout the lung parenchyma, but its distribution was not changed by ADSS exposure. Isozyme CYP2E1 was also found in airway epithelial cells, b...