Biomaterial Database

Distribution and inhibition of dihydrouracil dehydrogenase activities in human tissues using 5-fluorouracil as a substrate. 1986

D H Ho, and L Townsend, and M A Luna, and G P Bodey

Dihydrouracil dehydrogenase activity, with 5-fluorouracil used as the substrate, was measured in human tissues and leukemic cells. The liver had the highest enzyme activity (mean, 705 nmoles/g tissue/hr) with minimal activity found in the kidneys, spleen, lung, colon, colon tumors, pancreas, breast tissue, breast tumors, bone marrow cells, and peripheral leukemic cells. Wide variations in the enzyme activities were noted in samples collected from different subjects. 5-diazouracil inhibits the enzyme activity with the concentration required for inhibiting 50% (IC50) of the liver enzyme being 3 microM. Other compounds, thymine, thymidine, 6-methoxydiazouracil, and cyclo-5-diazouridine were also tested for their effect on this enzyme. With the exception of cyclo-5-diazouridine, all others produced inhibitory effect. The inhibitory effect of 6-methoxydiazouracil is similar to that of diazouracil. Thymidine and thymine are less active with identical values for IC50 of 80 microM.

UI	MeSH Term	Description	Entries
D008099	Liver	A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances.	Livers
D010088	Oxidoreductases	The class of all enzymes catalyzing oxidoreduction reactions. The substrate that is oxidized is regarded as a hydrogen donor. The systematic name is based on donor:acceptor oxidoreductase. The recommended name will be dehydrogenase, wherever this is possible; as an alternative, reductase can be used. Oxidase is only used in cases where O2 is the acceptor. (Enzyme Nomenclature, 1992, p9)	Dehydrogenases,Oxidases,Oxidoreductase,Reductases,Dehydrogenase,Oxidase,Reductase
D005472	Fluorouracil	A pyrimidine analog that is an antineoplastic antimetabolite. It interferes with DNA synthesis by blocking the THYMIDYLATE SYNTHETASE conversion of deoxyuridylic acid to thymidylic acid.	5-FU,5-FU Lederle,5-FU Medac,5-Fluorouracil,5-Fluorouracil-Biosyn,5-HU Hexal,5FU,Adrucil,Carac,Efudex,Efudix,Fluoro-Uracile ICN,Fluoroplex,Fluorouracil Mononitrate,Fluorouracil Monopotassium Salt,Fluorouracil Monosodium Salt,Fluorouracil Potassium Salt,Fluorouracil-GRY,Fluorouracile Dakota,Fluorouracilo Ferrer Far,Fluoruracil,Fluracedyl,Flurodex,Haemato-FU,Neofluor,Onkofluor,Ribofluor,5 FU Lederle,5 FU Medac,5 Fluorouracil,5 Fluorouracil Biosyn,5 HU Hexal,Dakota, Fluorouracile,Fluoro Uracile ICN,Fluorouracil GRY,Haemato FU
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D006863	Hydrogen-Ion Concentration	The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH	pH,Concentration, Hydrogen-Ion,Concentrations, Hydrogen-Ion,Hydrogen Ion Concentration,Hydrogen-Ion Concentrations
D013936	Thymidine	A nucleoside in which THYMINE is linked to DEOXYRIBOSE.	2'-Deoxythymidine,Deoxythymidine,2' Deoxythymidine
D013941	Thymine	One of four constituent bases of DNA.	5-Methyluracil,5 Methyluracil
D014498	Uracil	One of four nucleotide bases in the nucleic acid RNA.
D044925	Oxidoreductases Acting on CH-CH Group Donors	A subclass of enzymes which includes all dehydrogenases acting on carbon-carbon bonds. This enzyme group includes all the enzymes that introduce double bonds into substrates by direct dehydrogenation of carbon-carbon single bonds.	Oxidoreductases Acting on CH CH Group Donors
D050744	Dihydrouracil Dehydrogenase (NAD+)	An enzyme that catalyzes the oxidation of 5,6-dihydrouracil to URACIL using NAD as a cofactor. This enzyme also plays a role in the catabolism of the antimetabolite 5-FLUOROURACIL.	Dihydrothymine Dehydrogenase (NAD),Dihydrouracil Dehydrogenase,Dihydrouracil Dehydrogenase (NAD),Dehydrogenase, Dihydrouracil