Biological (molecular and cellular) markers of toxicity. Final report, September 15, 1988 - September 14, 1991
Several molecular and cellular markers of genotoxicity were adapted for measurement in the Medaka (Oryzias latipes), and were used to describe the effects of treatment of the organism with diethylnitrosamine (DEN). NO{sup 6}-ethyl guanine adducts were detected, and a slight statistically significant, increase in DNA strand breaks was observed. These results are consistent with the hypothesis that prolonged exposure to high levels of DEN induced alkyltransferase activity which enzymatically removes any O{sup 6}-ethyl guanine adducts but does not result in strand breaks or hypomethylation of the DNA such as might be expected from excision repair of chemically modified DNA. Following a five week continuous DEN exposure with 100 percent renewal of DEN-water every third day, the F values (DNA double strandedness) increased considerably and to similar extent in fish exposed to 25, 50, and 100 ppM DEN. This has been observed also in medaka exposed to BaP.
- Research Organization:
- Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
- Sponsoring Organization:
- Department of Defense (DOD), Washington, DC (United States)
- DOE Contract Number:
- AC05-84OR21400
- OSTI ID:
- 7044713
- Report Number(s):
- ORNL/M-1845; ON: DE92019190
- Country of Publication:
- United States
- Language:
- English
Similar Records
Estradiol-induced promotion of hepatocarcinogenesis in medaka: Relationship of foci of cellular alteration to neoplasia
Biological (molecular and cellular) markers of toxicity
Related Subjects
CARCINOGEN SCREENING
CARCINOGENS
BIOASSAY
MUTAGEN SCREENING
MUTAGENS
TERATOGEN SCREENING
TERATOGENS
BENZOPYRENE
BIOLOGICAL INDICATORS
DNA ADDUCTS
FISHES
NITROSAMINES
PROGRESS REPORT
ADDUCTS
AMINES
ANIMALS
AQUATIC ORGANISMS
AROMATICS
CONDENSED AROMATICS
DOCUMENT TYPES
HYDROCARBONS
NITROSO COMPOUNDS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
SCREENING
VERTEBRATES
560300* - Chemicals Metabolism & Toxicology