Carcinogenesis, Vol 18, 2239-2245, Copyright © 1997 by Oxford University Press
J Jiao, GR Douglas, JD Gingerich and LM Soper
N-Nitrosodibenzylamine (NDBzA) is a contaminant found frequently in rubber
baby bottle nipples and pacifiers. To evaluate more fully the mutagenic
potential and analyse the molecular nature of possible mutations induced in
vivo, we have studied the mutagenicity of NDBzA in vivo using the MutaMouse
system. NDBzA, suspended in olive oil, was administered orally once to male
mice at different doses (0, 30, 100, 425 and 750 mg/kg) and the mice were
killed 30 and 90 days after treatment. As a positive control, and to
compare relative mutagenicity, N-nitrosodimethylamine (NDMA) was also
administered to animals in the same experiment at doses of 0, 2, 6 and 10
mg/kg. Mutant frequencies were increased in both 30 and 90 day liver
samples, but not in bone marrow, after both NDBzA and NDMA treatment.
However, NDBzA was >100 times less mutagenic than NDMA. A total of 81
mutants obtained from liver samples of treated animals (750 mg/kg) were
characterized by DNA sequencing. While spontaneous mutations in transgenic
mice have been characterized previously by a preponderance of G:C-->A:T
transitions, mainly at 5'-CpG-3' dinucleotide sites, the predominant type
of NDBzA- induced mutation in this study was transversion, mainly
G:C-->T:A changes. The molecular characteristics of mutations induced by
NDBzA indicate that they may arise from specific unidentified DNA adducts
and benzylation appears to be the primary mechanism involved in formation
of these DNA adducts.
ARTICLES
Analysis of tissue-specific lacZ mutations induced by N- nitrosodibenzylamine in transgenic mice
Mutagenesis Section, Environmental Health Directorate, Health Canada, Ottawa, Ontario.
![]()
CiteULike
Connotea
Del.icio.us What's this?
This article has been cited by other articles:
![]() |
A. R. Clarke Manipulating the germline: its impact on the study of carcinogenesis Carcinogenesis, March 1, 2000; 21(3): 435 - 441. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. E.T. Dolle, H.-J. Martus, M. Novak, N. J. van Orsouw, and J. Vijg Characterization of color mutants in lacZ plasmid-based transgenic mice, as detected by positive selection Mutagenesis, May 1, 1999; 14(3): 287 - 293. [Abstract] [Full Text] [PDF] |
||||

