[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 bronchoalveolar 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.


CONCLUSIONS
Lower dose quartz has very strong toxicity to the lungs leading to pulmonary fibrosis.
D000818:Animals; D001194:Asbestos / Q000633:toxicity; D001992:Bronchoalveolar Lavage Fluid / Q000737:chemistry; D004391:Dust; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D008168:Lung / Q000473:pathology*; D008297:Male; D011658:Pulmonary Fibrosis / Q000209:etiology; D011791:Quartz / Q000633:toxicity*; D051381:Rats; D017208:Rats, Wistar