title: Use of rat primary lung cells for studying genotoxicity with the sister-chromatid exchange and micronucleus assays.
abstract: Primary culture of lung cells from CD rats was established for pulmonary genotoxicity studies using two genetic endpoints, sister-chromatid exchange (SCE) and micronucleus formation (MN). In the cell isolation study, a combined enzyme separation of rat lungs with trypsin (1.3 mg/ml) plus collagenase (50 U/ml) gave the highest yield of viable and colony-forming cells. For the MN assay, the cytokinesis block induced by cytochalasin B (CYB) was employed to enumerate MN in binucleated (BN) cells. Treatment of primary lung cells with 2 micrograms CYB/ml for two days appeared to be optimal for scoring micronuclei in CYB-induced BN cells. By this procedure, mitomycin C (MMC), triethylenemelamine, and benzo[a]pyrene caused a dose-related increase in micronucleated BN cells in vitro without metabolic activation. In the SCE assay, maximum second-division metaphases were obtained after cells were incubated with bromodeoxyuridine for 48-54 h. After this incubation time, high frequencies of SCE induced by MMC and 3-methylcholanthrene after in vitro exposure (without S9 activation) or in vivo exposure were observed. The results indicate that rat primary lung cells can metabolize polycyclic aromatic hydrocarbons and that this lung cell system is potentially useful for the detection of pulmonary genotoxicants.
authors.affiliation: Division of Respiratory Disease Studies, National Institute for Occupational Safety and Health, Morgantown, WV 26505-2888.
authors.forename: W Z
authors.initials: WZ
authors.lastname: Whong
authors.forename: J D
authors.initials: JD
authors.lastname: Stewart
authors.forename: T
authors.initials: T
authors.lastname: Ong
mesh_terms: D000818:Animals; D001564:Benzo(a)pyrene / Q000633:toxicity; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D003571:Cytochalasin B / Q000633:toxicity; D004305:Dose-Response Relationship, Drug; D008168:Lung / Q000187:drug effects*; D008297:Male; D008748:Methylcholanthrene / Q000633:toxicity; D015162:Micronucleus Tests / Q000379:methods*; D008937:Mitomycins / Q000633:toxicity; D051381:Rats; D011919:Rats, Inbred Strains; D012854:Sister Chromatid Exchange / Q000187:drug effects*; D014265:Triethylenemelamine / Q000633:toxicity
chemical_list: D008937:Mitomycins; D001564:Benzo(a)pyrene; D003571:Cytochalasin B; D008748:Methylcholanthrene; D014265:Triethylenemelamine