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| Predicate | Object |
|---|---|
| rdf:type | |
| lifeskim:mentions | |
| pubmed:issue |
39
|
| pubmed:dateCreated |
1996-11-18
|
| pubmed:databankReference | |
| pubmed:abstractText |
The inducible isoform II of nitric-oxide synthase (iNOS) was recently cloned from brain and identified in astroglial cells. Induced nitric oxide biosynthesis occurs in brain cells only if extracellular cerebrospinal fluid contains -arginine. This study demonstrates for the first time that induced iNOS activity is strictly dependent on concomitant induction of an alternatively spliced transcript of the cat-2 gene encoding high affinity -arginine transporter System y+ in cultured rat astrocytes. Inhibition profiles of radiolabeled -arginine and -leucine uptake identified the dominance of Na+-independent transport System y+ serving cationic amino acids, with insignificant activities of Systems y+L, bo,+, or Bo,+. A reverse transcription-polymerase chain reaction/sequencing/cloning strategy was used to identify a single 123-base nucleotide sequence coding the high affinity domain of alternatively spliced CAT-2 (not CAT-2a) in astrocytes activated by lipopolysaccharide/interferon-gamma. Using this sequence as a cDNA probe, it was determined that CAT-2 mRNA, iNOS mRNA, and System y+ activity were concomitantly and strongly induced in astrocytes. Constitutive CAT-1 mRNA was weakly present in neurons and astrocytes, was not inducible in either cell type, and contributed <3% to total System y+ activity. Although astroglial iNOS Km approximately 10 microM L-arginine for intracellular substrate, hyperbolic kinetics of inducible iNOS activity measured as a function of extracellular L-arginine concentration gave Km approximately 50 microM L-arginine with intact cells. The same Km approximately 50 microM was obtained for induced membrane transport System y+ activity. iNOS activity was reduced to zero in the absence of extracellular L-arginine uptake via System y+. These findings expand the current understanding of NO biosynthesis modulation and implicate a coordinated regulation of intracellular iNOS enzyme activity with membrane L-arginine transport in brain.
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| pubmed:grant | |
| pubmed:language |
eng
|
| pubmed:journal | |
| pubmed:citationSubset |
IM
|
| pubmed:chemical |
http://linkedlifedata.com/resource/pubmed/chemical/Arginine,
http://linkedlifedata.com/resource/pubmed/chemical/Carrier Proteins,
http://linkedlifedata.com/resource/pubmed/chemical/Interferon-gamma,
http://linkedlifedata.com/resource/pubmed/chemical/Lipopolysaccharides,
http://linkedlifedata.com/resource/pubmed/chemical/Membrane Glycoproteins,
http://linkedlifedata.com/resource/pubmed/chemical/Membrane Proteins,
http://linkedlifedata.com/resource/pubmed/chemical/Nitric Oxide,
http://linkedlifedata.com/resource/pubmed/chemical/Nitric Oxide Synthase,
http://linkedlifedata.com/resource/pubmed/chemical/RNA, Messenger,
http://linkedlifedata.com/resource/pubmed/chemical/Receptors, Virus,
http://linkedlifedata.com/resource/pubmed/chemical/Recombinant Proteins,
http://linkedlifedata.com/resource/pubmed/chemical/ecotropic murine leukemia virus...
|
| pubmed:status |
MEDLINE
|
| pubmed:month |
Sep
|
| pubmed:issn |
0021-9258
|
| pubmed:author | |
| pubmed:issnType |
Print
|
| pubmed:day |
27
|
| pubmed:volume |
271
|
| pubmed:owner |
NLM
|
| pubmed:authorsComplete |
Y
|
| pubmed:pagination |
24017-22
|
| pubmed:dateRevised |
2011-11-17
|
| pubmed:meshHeading |
pubmed-meshheading:8798637-Alternative Splicing,
pubmed-meshheading:8798637-Amino Acid Sequence,
pubmed-meshheading:8798637-Animals,
pubmed-meshheading:8798637-Arginine,
pubmed-meshheading:8798637-Astrocytes,
pubmed-meshheading:8798637-Base Sequence,
pubmed-meshheading:8798637-Biological Transport,
pubmed-meshheading:8798637-Brain,
pubmed-meshheading:8798637-Carrier Proteins,
pubmed-meshheading:8798637-Cell Membrane,
pubmed-meshheading:8798637-Enzyme Induction,
pubmed-meshheading:8798637-Gene Expression,
pubmed-meshheading:8798637-Interferon-gamma,
pubmed-meshheading:8798637-Lipopolysaccharides,
pubmed-meshheading:8798637-Membrane Glycoproteins,
pubmed-meshheading:8798637-Membrane Proteins,
pubmed-meshheading:8798637-Molecular Sequence Data,
pubmed-meshheading:8798637-Nitric Oxide,
pubmed-meshheading:8798637-Nitric Oxide Synthase,
pubmed-meshheading:8798637-RNA, Messenger,
pubmed-meshheading:8798637-Rats,
pubmed-meshheading:8798637-Rats, Inbred WKY,
pubmed-meshheading:8798637-Receptors, Virus,
pubmed-meshheading:8798637-Recombinant Proteins
|
| pubmed:year |
1996
|
| pubmed:articleTitle |
Induced nitric oxide synthesis is dependent on induced alternatively spliced CAT-2 encoding L-arginine transport in brain astrocytes.
|
| pubmed:affiliation |
Department of Physiology, College of Medicine, University of Florida, Gainesville, Florida 32610-0274, USA.
|
| pubmed:publicationType |
Journal Article,
Research Support, U.S. Gov't, P.H.S.,
Research Support, Non-U.S. Gov't
|