TY  - JOUR
A1  - Shephard, S. E.
A1  - Sengstag, C.
A1  - Lutz, Werner K.
A1  - Schlatter, C.
T1  - Mutations in liver DNA of lacI transgenic mice (Big Blue) following subchronic exposure to 2-acetylaminofluorene
N2  - 2-Acetylaminofluorene (2-AAF) was administered at Ievels of 0, 300 and 600 ppm in the diet for 28 days to female transgenic micc bearing the lacl genein a Iambda vector (Big Blue® mice). The Iambda vector was excised from liver DNA and packaged in vitro into bacteriophage particles which were allowed to infect E. coli bacteria, forming plaques on agar plates. Approximately 10\(^5\) plaques wcre screened per animal for the appearance of a bluc colour, indicative of mutations in the lac/ gcnc which had resulted in an inactive gene product. Background mutation rate was 2.7 x 10\(^{-5}\) (pooled results of two animals, 8 mutant plaques/289 530 plaques). At 300 ppm in the diet, the rate of 3.5 X 10\(^{-5}\)(8/236 300) was not significantly increased over background. At 600 ppm in the dict, the rate increased approximately 3 fold to 7.7 x 10\(^{-5}\) (17 /221240). In comparison to the usual single or 5-day carcinogen exposure regimes, the 4-week exposure protocol allowed the use of much lower dose Ievels 00-1000 fold lower). Overt toxicity could thus be avoided. The daily doses used were somewhat higher than those required in 2-year carcinogenicity studies with 2·AAF.
KW  - Toxikologie
KW  - 2-Acetylaminofluorene
KW  - Transgenic mouse
KW  - Mutation assay
KW  - in vivo
KW  - Dose response
Y1  - 1993
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-60683
ER  -