Evaluation of phenobarbital/beta-naphthoflavone as an alternative S9-induction regime to Aroclor 1254 in the rat for use in in vitro genotoxicity assays.
A series of bacterial mutation, mammalian cell (L5178Y) gene mutation and in vitro cytogenetic assays were performed to compare the efficacy of using S9 fractions prepared from rats induced with a combination of phenobarbital (PB) and beta-naphthoflavone (beta NF), with S9 fractions from rats treated with the general enzyme inducer Aroclor 1254. Although some quantitative differences in the magnitudes of the mutagenic/clastogenic effects were observed between the two induction regimes, no qualitative differences were observed. The use of a combined PB/beta NF induction regime using oral dosing is therefore considered to be a suitable substitute for Aroclor 1254.
Callander
R D
RD
ZENECA Central Toxicology Laboratory, Macclesfield, Cheshire, UK.
Mackay
J M
JM
Clay
P
P
Elcombe
C R
CR
Elliott
B M
BM
D000284:Administration, Oral; D000818:Animals; D001140:Aroclors / Q000633:toxicity*; D001564:Benzo(a)pyrene / Q000633:toxicity; D001571:Benzoflavones / Q000008:administration & dosage / Q000633:toxicity*; D002273:Carcinogens / Q000633:toxicity; D020111:Chlorodiphenyl (54% Chlorine); D002869:Chromosome Aberrations; D003577:Cytochrome P-450 Enzyme System / Q000187:drug effects / Q000378:metabolism; D004128:Dimethylnitrosamine / Q000633:toxicity; D005260:Female; D006801:Humans; D008110:Liver Extracts / Q000378:metabolism*; D008214:Lymphocytes / Q000166:cytology / Q000187:drug effects; D008297:Male; D009152:Mutagenicity Tests / Q000379:methods*; D010634:Phenobarbital / Q000008:administration & dosage / Q000633:toxicity*; D051381:Rats; D012486:Salmonella typhimurium / Q000187:drug effects / Q000235:genetics; D019324:beta-Naphthoflavone
D001140:Aroclors; D001571:Benzoflavones; D002273:Carcinogens; D008110:Liver Extracts; D020111:Chlorodiphenyl (54% Chlorine); D001564:Benzo(a)pyrene; D019324:beta-Naphthoflavone; D003577:Cytochrome P-450 Enzyme System; D004128:Dimethylnitrosamine; D010634:Phenobarbital