Metabolic functions of alveolar type II cells in acute silicosis.
Levy-RD; Hubbs-AF; Ducatman-BS; Singh-G; Vallyathan-V; Bowman-L; Miles-PR
Toxicologist 1997 Mar; 36(1)(Part 2):74
We have examined some metabolic functions of alveolar type II cells during experimental silicosis in rats. Consistent with previous studies, hypertrophied and hyperplastic alveolar type II cells and alveolar lipoproteinosis were observed at two and four weeks after intratracheal administration of 20 mg silica. Both hypertrophied and normal alveolar type II cells from all exposure groups contained immunohistochemically detectable lysozyme and surfactant apoprotein. Cytochrome P450 28 I was immunohistochemically demonstrated in the Clara and normal type II cells of control and silica exposed rat lungs. However, the hypertrophied and hyperplastic alveolar type II cells contained no immunohistochemically detectable cytochrome P450 281. The concentration of P450 281 containing alveolar cells (positive cells/mm2) was unaltered by silica. These findings support the hypothesis that during experimental silicosis, the hypertrophied type II cells are a newly-induced population of alveolar cells metabolically distinct from the pre-existing type II cells.
Toxic-dose; Toxic-materials; Toxins; Exposure-assessment; Exposure-levels; Exposure-limits; Alveolar-cells; Lung-tissue; Lung-disorders; Lung-cells; Respiratory-system-disorders; Pulmonary-system-disorders; Silicates; Silica-dusts; Silicosis
The Toxicologist. Society of Toxicology 36th Annual Meeting, March 9-13, 2006, Cincinnati, Ohio