Biomaterial Database

Mutagenesis by N-acetoxy-2-acetyl aminofluorene of chinese hamster V79 cells is unaffected by caffeine. 1978

B C Myhr, and J A Dipaolo

8-Azaguanine (AZG)- and 6-thioguanine (TG)-resistant cells (mutants) were induced in Chinese hamster V79-4 cells by 0.1--2.5 microgram/ml N-acetoxy-2-acetyle aminofluorine (AcAAF) treatments in the presence of 5% fetal bovine serum (FBS). The frequency of resistant colonies increased from 1 to 47 per 10(5) survivors. The effect of caffeine (50--200 microgram/ml) during the mutagenesis expression period was determined by adding caffeine 1--24 h after AcAAF. The medium was replaced after 48 h exposures so that caffeine was absent during subsequent selection with AZG or TG. No significant change in the AcAAF-induced mutant frequency occurred with any treatment combination although caffeine greatly enhanced the lethality associated with AcAAF treatments. Thus, caffeine interferes with postreplication repair in V79-4 cells without affecting the probability of error of the repair process. These results were obtained with a quantitative mutagenesis assay in which the cells were reseeded prior to selection to achieve maximum expression without interference from metabolic crossfeeding. In contrast, the commonly used in situ assay is subject to serious interference from crossfeeding and yields an artifactual enhancement of AcAAF mutagenesis by caffeine.

UI	MeSH Term	Description	Entries
D009153	Mutagens	Chemical agents that increase the rate of genetic mutation by interfering with the function of nucleic acids. A clastogen is a specific mutagen that causes breaks in chromosomes.	Clastogen,Clastogens,Genotoxin,Genotoxins,Mutagen
D002110	Caffeine	A methylxanthine naturally occurring in some beverages and also used as a pharmacological agent. Caffeine's most notable pharmacological effect is as a central nervous system stimulant, increasing alertness and producing agitation. It also relaxes SMOOTH MUSCLE, stimulates CARDIAC MUSCLE, stimulates DIURESIS, and appears to be useful in the treatment of some types of headache. Several cellular actions of caffeine have been observed, but it is not entirely clear how each contributes to its pharmacological profile. Among the most important are inhibition of cyclic nucleotide PHOSPHODIESTERASES, antagonism of ADENOSINE RECEPTORS, and modulation of intracellular calcium handling.	1,3,7-Trimethylxanthine,Caffedrine,Coffeinum N,Coffeinum Purrum,Dexitac,Durvitan,No Doz,Percoffedrinol N,Percutaféine,Quick-Pep,Vivarin,Quick Pep,QuickPep
D002478	Cells, Cultured	Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.	Cultured Cells,Cell, Cultured,Cultured Cell
D003412	Cricetulus	A genus of the family Muridae consisting of eleven species. C. migratorius, the grey or Armenian hamster, and C. griseus, the Chinese hamster, are the two species used in biomedical research.	Hamsters, Armenian,Hamsters, Chinese,Hamsters, Grey,Armenian Hamster,Armenian Hamsters,Chinese Hamster,Chinese Hamsters,Grey Hamster,Grey Hamsters,Hamster, Armenian,Hamster, Chinese,Hamster, Grey
D004347	Drug Interactions	The action of a drug that may affect the activity, metabolism, or toxicity of another drug.	Drug Interaction,Interaction, Drug,Interactions, Drug
D005449	Fluorenes	A family of diphenylenemethane derivatives.
D006224	Cricetinae	A subfamily in the family MURIDAE, comprising the hamsters. Four of the more common genera are Cricetus, CRICETULUS; MESOCRICETUS; and PHODOPUS.	Cricetus,Hamsters,Hamster
D000099	Acetoxyacetylaminofluorene	An alkylating agent that forms DNA ADDUCTS at the C-8 position in GUANINE, resulting in single strand breaks. It has demonstrated carcinogenic action.	Acetoxyacetamidofluorene,Acetoxyfluorenylacetamide,N-Acetoxy-2-acetylaminofluorene,N-Acetoxy-N-acetyl-2-aminofluorene,N Acetoxy 2 acetylaminofluorene,N Acetoxy N acetyl 2 aminofluorene
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D013997	Time Factors	Elements of limited time intervals, contributing to particular results or situations.	Time Series,Factor, Time,Time Factor