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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
34
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pubmed:dateCreated |
1987-1-7
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pubmed:abstractText |
Sodium-dependent beta-alanine uptake into dog renal brush-border membrane vesicles was studied. Kinetic analysis indicated a single transport system, highly specific for beta-amino acids, with Km = 35 microM at 100 mM NaCl. Sodium-dependent beta-alanine transport was markedly anion-dependent, being highest in the presence of chloride (Cl greater than Br greater than SCN greater than NO3 approximately I greater than F) and virtually nonexistent in the presence of gluconate and other nonphysiological chloride substitutes. In addition, it was observed that beta-alanine uptake could be driven against a concentration gradient by a chloride gradient. Similar results were found for sodium. Taken together, these observations provide strong evidence that beta-alanine transport across the renal brush-border membrane is coupled to both sodium and chloride. Studies of the dependence of beta-alanine flux on chloride and sodium concentrations indicated that one chloride ion and multiple sodium ions were involved in the beta-alanine transport event. beta-Alanine flux on chloride found to involve the net transfer of positive charge, consistent with these stoichiometric assignments. The hallucinogen harmaline inhibited beta-alanine uptake in a 1:1 fashion, presumably by acting at a single site on the transport molecule. The ability of harmaline to inhibit beta-alanine uptake was decreased when the chloride concentration was lowered but was unchanged when the sodium concentration was decreased. These results indicate that harmaline does not compete with sodium for a binding site on the carrier as has been suggested for other sodium-coupled transport systems, and that instead, chloride may be required for harmaline binding to the beta-alanine transporter.
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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/Alanine,
http://linkedlifedata.com/resource/pubmed/chemical/Anions,
http://linkedlifedata.com/resource/pubmed/chemical/Chlorides,
http://linkedlifedata.com/resource/pubmed/chemical/Harmaline,
http://linkedlifedata.com/resource/pubmed/chemical/Sodium,
http://linkedlifedata.com/resource/pubmed/chemical/beta-Alanine
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pubmed:status |
MEDLINE
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pubmed:month |
Dec
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pubmed:issn |
0021-9258
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pubmed:author | |
pubmed:issnType |
Print
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pubmed:day |
5
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pubmed:volume |
261
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
16060-6
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pubmed:dateRevised |
2006-11-15
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pubmed:meshHeading |
pubmed-meshheading:3096999-Alanine,
pubmed-meshheading:3096999-Animals,
pubmed-meshheading:3096999-Anions,
pubmed-meshheading:3096999-Biological Transport,
pubmed-meshheading:3096999-Chlorides,
pubmed-meshheading:3096999-Dogs,
pubmed-meshheading:3096999-Dose-Response Relationship, Drug,
pubmed-meshheading:3096999-Harmaline,
pubmed-meshheading:3096999-Kidney,
pubmed-meshheading:3096999-Membrane Potentials,
pubmed-meshheading:3096999-Microvilli,
pubmed-meshheading:3096999-Sodium,
pubmed-meshheading:3096999-beta-Alanine
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pubmed:year |
1986
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pubmed:articleTitle |
beta-Amino acid transport across the renal brush-border membrane is coupled to both Na and Cl.
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pubmed:publicationType |
Journal Article,
In Vitro,
Research Support, Non-U.S. Gov't
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