Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1990-5-29
pubmed:abstractText
The synergistic effect of NADPH and NADH on P450 functions upon pre-mutagens requiring metabolism during the incubation conditions used in the liver microsomal assay (LMA) was studied. The mean specific activity (Asp) during 1 h of pre-incubation (LMA) of some microsomal mono-oxygenases (i.e. ethylmorphine N-demethylase, p-nitroanisole O-demethylase and aminopyrine N-demethylase) examined with S9 fractions from sodium phenobarbital and beta-naphthoflavone pre-treated mice, was doubled when both NADPH and NADH were present. In contrast, when lipid peroxidation was used as the main enzymatic inactivation index, there was no appreciable change. In agreement with biochemical data, in vitro DNA binding of the pre-mutagenic agent [14C]-1,1,1,2-tetrachloroethane ([14C]TTCE), mediated by mouse hepatic enzymes, showed a significant enhancement (4.4-fold) of specific activity in the presence of both pyridine nucleotides. Mutagenesis experiments using TTCE in the diploid D7 strain of Saccharomyces cerevisiae (from stationary growth phase) as a biological test system, showed a significant enhancement of mitotic gene conversion and reverse point mutation frequencies when using NADPH plus NADH in the medium. Conversely, no positive results without NADH were seen. These findings lead us to suggest the routine use of both NADPH and NADH in order to increase the 'sensitivity' of in vitro mutagenicity screens.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0267-8357
pubmed:author
pubmed:issnType
Print
pubmed:volume
5
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
51-4
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1990
pubmed:articleTitle
Strategies for optimization of short-term genotoxicity tests: the synergistic effect of NADPH and NADH on P450 function in processing pre-mutagens.
pubmed:affiliation
Istituto di Farmacologia dell Universita, Bologna, Italy.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't