Friemann J, Albrecht C, Breuer P, Grover R, Weishaupt C
Department of Environmental Pathology, Medical Institute of Environmental Hygiene, Heinrich Heine University, Düsseldorf, Germany.
Inhal Toxicol. 1999 Sep;11(9):837-54. doi: 10.1080/089583799196763.
In this study, we compared the morphological reaction patterns in rat lungs following a single intratracheal instillation of 20 mg quartz, 20 mg coal mine dust (15.3% quartz), or 25 mg talc. Control animals received a single dose of 0.5 ml saline solution intratracheally. Investigations by light microscopy, morphometry, and DNA image cytometry were carried out 3, 6, 12, and 18 mo after dust administration. During the investigation period, we observed a temporary increase in the number, area, and proliferative activity of the type II cells, which differed in intensity among the three dusts. After 18 mo, however, type II cells in treated animals did not differ from control animals. On the other hand, the expansion of a multifocal alveolar bronchiolization as putative preneoplastic lesion had progressed enormously by the end of the test (1-3% of the investigated lung area). Consistent with this, the proliferative activity of the epithelial cells in terminal bronchi of the coal mine dust- and quartz-treated animals was enhanced by the end of the 18-mo investigation period, while the reaction to talc was minimal (0.2% of totally investigated lung area). Our data suggest that in bronchiolo-alveolar regions, especially in the epithelium of terminal bronchi, there is an overshoot regeneration after cell damage that leads to an alveolar bronchiolization.
在本研究中，我们比较了大鼠经气管内单次注入20毫克石英、20毫克煤矿粉尘（15.3%石英）或25毫克滑石粉后肺组织的形态学反应模式。对照动物经气管内单次给予0.5毫升盐溶液。在给予粉尘后3、6、12和18个月进行了光学显微镜检查、形态测量和DNA图像细胞术分析。在研究期间，我们观察到II型细胞数量、面积和增殖活性出现暂时增加，三种粉尘之间这种增加的强度有所不同。然而，18个月后，处理组动物的II型细胞与对照动物并无差异。另一方面，作为假定癌前病变的多灶性肺泡细支气管化在试验结束时（占所研究肺面积的1 - 3%）有极大进展。与此一致的是，在18个月的研究期结束时，煤矿粉尘和石英处理组动物终末细支气管上皮细胞的增殖活性增强，而对滑石粉的反应最小（占所研究肺总面积的0.2%）。我们的数据表明，在细支气管肺泡区域，特别是终末细支气管上皮，细胞损伤后存在过度再生，导致肺泡细支气管化。
