title: Induction of sister-chromatid exchanges in human lymphocytes by indirect carcinogens with and without metabolic activation.
abstract: Sister-chromatid exchanges (SCEs) were examined in cultured human lymphocytes after exposure for 1 h to aflatoxin B1 (AFB1), Trp-P-1, Trp-P-2, dimethyl-nitrosamine (DMN), diethylnitrosamine (DEN) and benzo[a]pyrene (BP) with and without a metabolic activation system (S9 mix). With metabolic activation, all the carcinogens produced significant and dose-dependent increases in SCE frequency. However, the molar concentrations that induced a 2-fold increase in SCEs per cell over the control level were distributed over a range of more than 10(4). Without metabolic activation, AFB1, at 10(-4) M, caused a significant increase in SCE induction, whereas the other compounds caused little or no increase in SCE frequency above the control levels.
mesh_terms: D016604:Aflatoxin B1; D000348:Aflatoxins / Q000633:toxicity; D001564:Benzo(a)pyrene; D001580:Benzopyrenes / Q000633:toxicity; D001711:Biotransformation; D002243:Carbolines / Q000633:toxicity; D002273:Carcinogens / Q000633:toxicity*; D002478:Cells, Cultured; D003434:Crossing Over, Genetic / Q000187:drug effects*; D004052:Diethylnitrosamine / Q000633:toxicity; D004128:Dimethylnitrosamine / Q000633:toxicity; D006801:Humans; D008214:Lymphocytes / Q000187:drug effects* / Q000502:physiology; D009153:Mutagens; D012854:Sister Chromatid Exchange / Q000187:drug effects*
chemical_list: D000348:Aflatoxins; D001580:Benzopyrenes; D002243:Carbolines; D002273:Carcinogens; D009153:Mutagens; D001564:Benzo(a)pyrene; D004052:Diethylnitrosamine; C019133:3-amino-1-methyl-5H-pyrido(4,3-b)indole; D016604:Aflatoxin B1; C019132:3-amino-1,4-dimethyl-5H-pyrido(4,3-b)indole; D004128:Dimethylnitrosamine