Pinkerton K E, Pratt P C, Brody A R, Crapo J D
Am J Pathol. 1984 Dec;117(3):484-98.
Inhalation of chrysotile asbestos fibers causes interstitial lung disease in animals and man. For examination of the anatomic localization of inhaled asbestos and its relationship to alveolar tissue responses of the lung during and after chronic exposure, male and female Fischer 344 rats were exposed to aerosolized chrysotile for 7 hours/day, 5 days/week for 3 or 12 months. A number of exposed animals were kept in filtered air for an additional 12 months. Lung tissue from randomly selected animals in each group was studied by morphometric analysis of electron micrographs. Our findings show that during exposure to asbestos fibers, macrophages and alveolar epithelial cells contain statistically significant amounts of asbestos and are associated with histologic changes indicating marked epithelial injury. Increased amounts of fibers are also localized in the lung interstitium with continued exposure to asbestos and are associated with a progressive interstitial fibrotic reaction. Following cessation of exposure, macrophages and epithelial cells are cleared of fibers and resolve toward normal proportions. However, significant clearance of fibers from the lung interstitium does not occur after cessation of exposure, and there is a continuing process of fibrogenesis. These data provide new insights related to the pathogenesis of diffuse lung disease and the role each alveolar tissue compartment plays in the early and late phases of the disease.
吸入温石棉纤维会在动物和人类中引发间质性肺病。为了研究吸入石棉的解剖学定位及其在慢性暴露期间和之后与肺部肺泡组织反应的关系，将雄性和雌性Fischer 344大鼠每天暴露于雾化温石棉中7小时，每周5天，持续3或12个月。一些暴露的动物在过滤空气中再饲养12个月。通过对电子显微镜照片进行形态计量分析，研究了每组中随机选择的动物的肺组织。我们的研究结果表明，在暴露于石棉纤维期间，巨噬细胞和肺泡上皮细胞含有统计学上显著量的石棉，并与表明明显上皮损伤的组织学变化相关。随着持续暴露于石棉，肺间质中纤维数量增加，并与进行性间质纤维化反应相关。停止暴露后，巨噬细胞和上皮细胞中的纤维被清除，比例恢复正常。然而，停止暴露后，肺间质中的纤维并没有显著清除，并且存在持续的纤维化过程。这些数据为弥漫性肺病的发病机制以及每个肺泡组织隔室在该疾病早期和晚期所起的作用提供了新的见解。
