title: A modified method of UDS detection in vitro suitable for screening the DNA-damaging effects of chemicals.
abstract: The UDS induced in cultured FL cells by exposure to chemicals was measured as hydroxyurea-resistant incorporation of 3H-TdR in the acid-insoluble fraction of the 14C-TdR-prelabelled cells synchronized by the combination of arginine starvation and pretreatment with hydroxyurea. The level of UDS is represented by the ratios of 3H/14C radioactivities which are measures of specific activities of 3H. Two direct-acting alkylating agents, MMS and MNNG, a cross-linking agent, mitomycin C, and 3 procarcinogens, B(a)P, AFB1 and cyclophosphamide elicited UDS in the absence or presence of the liver-metabolizing system. Three chemicals of unknown carcinogenicity were also able to induce UDS in this assay system, i.e., bis-(O,O-diethylphosphinothioyl)-disulphide, 4-chlorophenoxy acetic acid (sodium salt) and caramelized malt sugar. With the exception of 4-chlorophenoxy acetic acid, they were also active in the Ames test.
mesh_terms: D000650:Amnion; D002273:Carcinogens / Q000633:toxicity*; D002460:Cell Line; D004261:DNA Replication / Q000187:drug effects*; D005260:Female; D006801:Humans; D006918:Hydroxyurea / Q000633:toxicity; D007700:Kinetics; D009152:Mutagenicity Tests; D009153:Mutagens / Q000633:toxicity*; D009154:Mutation; D011247:Pregnancy
chemical_list: D002273:Carcinogens; D009153:Mutagens; D006918:Hydroxyurea