title: Post-treatments with sodium arsenite during G2 enhance the frequency of chromosomal aberrations induced by S-dependent clastogens.
abstract: Treatment with sodium arsenite during the G2 phase potentiated the chromatid breaks and chromatid exchanges induced by ultraviolet light or 4-nitroquinoline 1-oxide but not those induced by methyl methanesulfonate, ethyl methanesulfonate, mitomycin C or cisplatin in Chinese hamster ovary cells. A comparison was made between the effects of treatment during G2 with sodium arsenite, cytosine-beta-D-arabinofuranoside, aphidicolin, hydroxyurea, caffeine, 3-aminobenzamide and novobiocin on the frequency of chromosomal aberrations induced by the above-mentioned S-dependent clastogens. It was found that the effects varied considerably, both quantitatively and qualitatively. However, potentiation was more often observed in the chromosomal aberrations induced by ultraviolet light and 4-nitroquinoline 1-oxide than by other S-dependent clastogens, and the frequency of chromatid exchanges was potentiated only in cells pretreated with ultraviolet light or 4-nitroquinoline 1-oxide. Furthermore, for all of the S-dependent clastogens studied, treatment with cytosine-beta-D-arabinofuranoside during the G2 phase potentiated the frequency of chromatid breaks but not the frequency of chromatid exchanges.
mesh_terms: D000818:Animals; D001151:Arsenic / Q000494:pharmacology*; D018053:Arsenites; D002460:Cell Line; D002842:Chromatids / Q000187:drug effects / Q000528:radiation effects; D002869:Chromosome Aberrations; D006224:Cricetinae; D004260:DNA Repair / Q000187:drug effects; D004357:Drug Synergism; D005260:Female; D007399:Interphase / Q000187:drug effects* / Q000528:radiation effects; D009153:Mutagens / Q000494:pharmacology*; D010053:Ovary; D017670:Sodium Compounds; D014466:Ultraviolet Rays
chemical_list: D018053:Arsenites; D009153:Mutagens; D017670:Sodium Compounds; C017947:sodium arsenite; D001151:Arsenic