Chromosomal aberrations and sister-chromatid exchanges induced by N-nitroso-2-acetylaminofluorene and their modifications by arsenite and selenite in Chinese hamster ovary cells.
The frequencies of chromosomal aberrations (CA) and sister-chromatid exchanges (SCE) in Chinese hamster cells were significantly increased by the direct-acting mutagen N-nitroso-2-acetylaminofluorene (N-NO-AAF) at the concentration of 0.1 mM. N-NO-AAF was prepared by nitrosation of the protohepatocarcinogen 2-acetylaminofluorene. The induced CA, which included chromatid breaks, chromatid exchanges, chromosome breaks, and chromosome ring formation were significantly potentiated by the presence of sodium arsenite (10 microM), but not by hydroxyurea (20 mM) or cytosine arabinoside (25 microM). On the other hand, the clastogenic effect of N-NO-AAF was effectively inhibited by sodium selenite (100 microM). Arsenite (10 microM) was shown to be moderately active in CA induction which was partially blocked by the presence of selenite (10 nM). N-Nitroso compounds such as N-nitroso-N-methylurea, N-nitroso-N-ethylurea and N-methyl-N'-nitro-N-nitrosoguanidine were equally or more active in the induction of CA and SCE in CHO cells when compared with N-NO-AAF. The cell cycle was significantly delayed by the intervention of N-NO-AAF.
Institute of Biochemistry, College of Medicine, National Taiwan University, Taipei, Republic of China.
J K
JK
Lin
S F
SF
Tseng
D015073:2-Acetylaminofluorene / Q000031:analogs & derivatives* / Q000037:antagonists & inhibitors / Q000633:toxicity; D000818:Animals; D001151:Arsenic / Q000494:pharmacology*; D018053:Arsenites; D016466:CHO Cells; D002453:Cell Cycle / Q000187:drug effects; D002869:Chromosome Aberrations; D006224:Cricetinae; D004347:Drug Interactions; D009153:Mutagens / Q000633:toxicity*; D009603:Nitroso Compounds / Q000037:antagonists & inhibitors / Q000633:toxicity*; D012643:Selenium / Q000494:pharmacology*; D012854:Sister Chromatid Exchange; D018038:Sodium Selenite
D018053:Arsenites; D009153:Mutagens; D009603:Nitroso Compounds; C057157:N-nitroso-N(2)-fluorenylacetamide; D015073:2-Acetylaminofluorene; D012643:Selenium; D018038:Sodium Selenite; C015001:arsenite; D001151:Arsenic