较低剂量石英粉尘所致大鼠肺脏的早期变化

目的研究较低剂量的石英对肺组织损伤的特点。方法对大鼠采用较低剂量的石英和石棉粉尘（每只１０ｍｇ）染尘后，测定两种粉尘在两个月内所致大鼠支气管肺泡灌洗液中细胞总数、蛋白含量、总脂含量和乳酸脱氢酶（ＬＤＨ）活性等毒性指标以及全肺胶原含量的变化，并观察肺组织的病理改变。结果石英可引起灌洗液中细胞总数、蛋白质含量、总脂含量和ＬＤＨ活性持续升高，全肺胶原含量持续增加；而石棉只引起细胞总数和ＬＤＨ在染尘后１０天的一过性升高，全肺胶原含量虽也逐渐增加，但不如石英明显。结论较低剂量的石英具有很强的肺毒性和致纤维化能力。

Early Changes in Rat Lungs Caused by Lower dose Quartz Dust

Objective To study the features of damages in the lungs caused by lower dose quartz. Methods Cell count, contents of protein and total lipid and activity of lactate dehydrogenase (LDH) in bronchoalveolar lavage, changes in content of collagen in the whole lungs of the rats were determined after their exposure to lower dose quartz and asbestosdust (10 mg per rat), and pathological changes in the lungs were also observed. Results Cell count, contents of protein and total lipid and activity of lactate dehydrogenase in brochoalveolar lavage, and content of total collagen in the whole lungs increased persistently in the rats exposed to quartz; and, only cell count and activity of lactate dehydrogenase increased transiently in rats 10 days after exposure to asbestos, and content of collagen also increased gradually, but not so obviously as caused by quartz. Conclusion Lowere dose quartz has very strong toxicity to the lungs leading to pulmonary fibrosis.