Source:http://linkedlifedata.com/resource/pubmed/id/15353477
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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
1
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pubmed:dateCreated |
2004-12-21
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pubmed:abstractText |
Erythrocyte magnesium (Mg2+) deficiency has been demonstrated in sickle cell disease to contribute to erythrocyte dehydration, K loss, and thus sickling. No studies have assessed the functional properties of the Na/Mg exchanger in sickle cell disease. Using Mg(2+)-loaded erythrocytes, we measured Mg2+ efflux induced by extracellular Na+. We estimated that the Na/Mg exchanger had higher maximal velocity, higher affinity for Na+, and lower cooperativity for Mg2+ in sickle than in normal erythrocytes. The activity of the exchanger was markedly decreased by hypotonic and hypertonic conditions in normal erythrocytes but not in sickle erythrocytes. Studies of density-separated erythrocytes showed that the activity of the exchanger decreased as the mean cellular hemoglobin concentration increased in normal but not in sickle erythrocytes. Inhibition of protein kinase C (PKC) activity by calphostin C and chelerythrine increased the activity of the exchanger in normal but not in sickle erythrocytes. Inhibition of serine/threonine phosphatases did not affect the activity of the exchanger in either normal or sickle erythrocytes. Altogether, these data indicate that the Na/Mg exchanger is abnormally regulated in sickle erythrocytes. Therefore, Mg2+ depletion in sickle erythrocytes might be mediated by an up-regulated Na/Mg exchanger, possibly by dephosphorylation of the transporter or a closely associated regulator.
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pubmed:grant | |
pubmed:language |
eng
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pubmed:journal | |
pubmed:citationSubset |
AIM
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pubmed:chemical |
http://linkedlifedata.com/resource/pubmed/chemical/Antiporters,
http://linkedlifedata.com/resource/pubmed/chemical/Enzyme Inhibitors,
http://linkedlifedata.com/resource/pubmed/chemical/Magnesium,
http://linkedlifedata.com/resource/pubmed/chemical/Phosphoric Monoester Hydrolases,
http://linkedlifedata.com/resource/pubmed/chemical/Protein Kinase C,
http://linkedlifedata.com/resource/pubmed/chemical/Sodium,
http://linkedlifedata.com/resource/pubmed/chemical/sodium-magnesium antiporter
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pubmed:status |
MEDLINE
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pubmed:month |
Jan
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pubmed:issn |
0006-4971
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pubmed:author | |
pubmed:issnType |
Print
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pubmed:day |
1
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pubmed:volume |
105
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
382-6
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pubmed:dateRevised |
2007-11-15
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pubmed:meshHeading |
pubmed-meshheading:15353477-Anemia, Sickle Cell,
pubmed-meshheading:15353477-Antiporters,
pubmed-meshheading:15353477-Enzyme Inhibitors,
pubmed-meshheading:15353477-Erythrocytes,
pubmed-meshheading:15353477-Humans,
pubmed-meshheading:15353477-Ion Transport,
pubmed-meshheading:15353477-Kinetics,
pubmed-meshheading:15353477-Magnesium,
pubmed-meshheading:15353477-Osmolar Concentration,
pubmed-meshheading:15353477-Phosphoric Monoester Hydrolases,
pubmed-meshheading:15353477-Phosphorylation,
pubmed-meshheading:15353477-Protein Kinase C,
pubmed-meshheading:15353477-Sodium
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pubmed:year |
2005
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pubmed:articleTitle |
Abnormal regulation of Mg2+ transport via Na/Mg exchanger in sickle erythrocytes.
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pubmed:affiliation |
Department of Laboratory Medicine, Children's Hospital Boston, Boston, MA 02115, USA. alicia.rivera@childrens.harvard.edu
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pubmed:publicationType |
Journal Article,
Research Support, U.S. Gov't, P.H.S.
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