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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
3
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pubmed:dateCreated |
1994-2-25
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pubmed:abstractText |
Nitric oxide (NO) is synthesized from L-arginine by different NO synthase isozymes, which are inhibited by the substrate analogs NG-methyl- and NG-nitro-L-arginine. We studied binding of 3H-labeled NG-nitro-L-arginine to purified brain NO synthase and compared the data with results obtained in enzyme kinetic experiments. Binding data revealed a single binding site for NG-nitro-L-[3H]arginine (KD = 0.17 microM). Binding was competitively antagonized by L-arginine (KI = 2.9 microM). The half-time of dissociation was remarkably slow (9.4 min) and closely correlated with the time necessary for surmounting NO synthase inhibition by dilution. Although an apparently less potent inhibitor, NG-methyl-L-arginine exhibited the same affinity for brain NO synthase as the nitro derivative (KI = 0.17 microM), and in initial rate experiments, almost equal KI values were obtained for NG-methyl-L-arginine (0.61 microM) and NG-nitro-L-arginine (0.53 microM). However, after prolonged incubation periods, NG-nitro-L-arginine induced a rapid inactivation of the enzyme, whereas the methyl derivative turned out to be a substrate of NO synthase, which was slowly converted into stoichiometric amounts of NO and L-citrulline.
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pubmed:language |
eng
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pubmed:journal | |
pubmed:citationSubset |
IM
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pubmed:chemical |
http://linkedlifedata.com/resource/pubmed/chemical/Amino Acid Oxidoreductases,
http://linkedlifedata.com/resource/pubmed/chemical/Arginine,
http://linkedlifedata.com/resource/pubmed/chemical/Nitric Oxide Synthase,
http://linkedlifedata.com/resource/pubmed/chemical/Nitroarginine,
http://linkedlifedata.com/resource/pubmed/chemical/omega-N-Methylarginine
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pubmed:status |
MEDLINE
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pubmed:month |
Jan
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pubmed:issn |
0021-9258
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pubmed:author | |
pubmed:issnType |
Print
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pubmed:day |
21
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pubmed:volume |
269
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
1674-80
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pubmed:dateRevised |
2006-11-15
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pubmed:meshHeading |
pubmed-meshheading:7507482-Amino Acid Oxidoreductases,
pubmed-meshheading:7507482-Animals,
pubmed-meshheading:7507482-Arginine,
pubmed-meshheading:7507482-Brain,
pubmed-meshheading:7507482-Chromatography, Gel,
pubmed-meshheading:7507482-Kinetics,
pubmed-meshheading:7507482-Nitric Oxide Synthase,
pubmed-meshheading:7507482-Nitroarginine,
pubmed-meshheading:7507482-Regression Analysis,
pubmed-meshheading:7507482-Swine,
pubmed-meshheading:7507482-omega-N-Methylarginine
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pubmed:year |
1994
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pubmed:articleTitle |
Inhibitors of brain nitric oxide synthase. Binding kinetics, metabolism, and enzyme inactivation.
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pubmed:affiliation |
Institut für Pharmakologie und Toxikologie, Karl-Franzens-Universität Graz, Austria.
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pubmed:publicationType |
Journal Article,
Research Support, Non-U.S. Gov't
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