Freshly Fractured Quartz Inhalation Leads to Enhanced Lung Injury and Inflammation. Potential Role of Free Radicals

作者：Val Vallyathan, Vincent Castranova, Donna Pack, Stephen S. Leonard, J.M. Shumaker, Ann F. Hubbs, Dale A. Shoemaker, Dawn M. Ramsey, Jack R. Pretty, Jeff McLaurin · 发表于：American Journal of Respiratory and Critical Care Medicine · 年份：1995 · DOI：10.1164/ajrccm.152.3.7663775 · 被引用次数：166 · 研究领域：Occupational and environmental lung diseases

Silicosis is a devastating pulmonary disease that continues to occur in industrial workplaces. Its pathogenesis is under critical evaluation, and this report provides new concepts on the possible early events that occur in lungs resulting from the inhalation of freshly fractured versus aged quartz in the development of two diverse disease entities. In this study, we evaluated the biochemical and pathologic changes in the lavagate and lungs of rats exposed to freshly fractured quartz (generated by jet milling), aged quartz (milled then aged for 2 mo prior to use), or clean air 5 h a day for 10 d over a 2-wk period. The concentration of crystalline quartz in the chambers averaged 20 mg/m3. Particle concentrations and particle size were similar for the freshly milled and aged quartz exposures. However, free radical concentrations associated with the freshly milled quartz samples were significantly higher than those for aged quartz. After a 2-wk exposure, animals were killed and studied by bronchoalveolar lavage and pulmonary histopathology. Inhalation of aged quartz increased the number of bronchoalveolar lavage cells, demonstrated histopathologic evidence of increased pulmonary infiltrates, showed enhanced concentrations of biochemical markers of lung injury, increased lipid peroxidation, and the ability of pulmonary phagocytes to produce more oxygen radicals. In general, all these pulmonary responses were significantly more pronounced after inhalation of freshly fractured quar...