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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
1
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pubmed:dateCreated |
1986-5-7
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pubmed:abstractText |
Energy-dependent Ca2+ uptake was characterized in vesicles derived from rat submandibular salivary glands. Ca2+ transport was stimulated by submicromolar levels of Ca2+, reached a plateau at 1-20 microM Ca2+ then again increased as the Ca2+ concentration rose to millimolar levels. Ruthenium red (2.5 microM) was used to resolve this pattern of uptake into two components: ruthenium red-insensitive Ca2+ transport occurs in the presence of the dye, is stimulated by submicromolar Ca2+ concentrations and reaches a maximum steady state at about 1 microM Ca2+. The distribution of ruthenium red-insensitive Ca2+ uptake in membrane subfractions obtained by differential centrifugation is positively (r = 0.717) and significantly (p = 0.001) correlated with the distribution of membrane-bound RNA in the same subfractions. Ca2+ uptake which is abolished by ruthenium red is greatest at millimolar Ca2+ concentrations. Its distribution is positively (r = 0.828) and significantly (p = 0.0001) correlated with the cytochrome-c oxidase activity of the membrane subfractions but is unrelated to the distribution of particulate RNA and is negatively correlated with Na+-K+ ATPase activity. We conclude that vesicles derived from the endoplasmic reticulum of rat submandibular glands actively transport Ca2+ by a ruthenium red-insensitive mechanism which is stimulated at Ca2+ concentrations typical of the cytosol. Membranes derived from mitochondria also sequester Ca2+ but by a mechanism which is inhibited by ruthenium red and which reaches its maximum steady state capacity at relatively high Ca2+ concentrations.
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pubmed:grant | |
pubmed:language |
eng
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pubmed:journal | |
pubmed:citationSubset |
IM
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pubmed:chemical |
http://linkedlifedata.com/resource/pubmed/chemical/Adenosine Triphosphate,
http://linkedlifedata.com/resource/pubmed/chemical/Calcimycin,
http://linkedlifedata.com/resource/pubmed/chemical/Calcium,
http://linkedlifedata.com/resource/pubmed/chemical/Magnesium,
http://linkedlifedata.com/resource/pubmed/chemical/RNA,
http://linkedlifedata.com/resource/pubmed/chemical/Ruthenium Red,
http://linkedlifedata.com/resource/pubmed/chemical/Sodium-Potassium-Exchanging ATPase
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pubmed:status |
MEDLINE
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pubmed:month |
Feb
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pubmed:issn |
0143-4160
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pubmed:author | |
pubmed:issnType |
Print
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pubmed:volume |
7
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
49-59
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pubmed:dateRevised |
2007-11-15
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pubmed:meshHeading |
pubmed-meshheading:2420466-Adenosine Triphosphate,
pubmed-meshheading:2420466-Animals,
pubmed-meshheading:2420466-Biological Transport, Active,
pubmed-meshheading:2420466-Calcimycin,
pubmed-meshheading:2420466-Calcium,
pubmed-meshheading:2420466-Cell Membrane,
pubmed-meshheading:2420466-Centrifugation,
pubmed-meshheading:2420466-Kinetics,
pubmed-meshheading:2420466-Magnesium,
pubmed-meshheading:2420466-Male,
pubmed-meshheading:2420466-RNA,
pubmed-meshheading:2420466-Rats,
pubmed-meshheading:2420466-Rats, Inbred Strains,
pubmed-meshheading:2420466-Ruthenium Red,
pubmed-meshheading:2420466-Sodium-Potassium-Exchanging ATPase,
pubmed-meshheading:2420466-Submandibular Gland
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pubmed:year |
1986
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pubmed:articleTitle |
Characterization and localization of two forms of active Ca2+ transport in vesicles derived from rat submandibular glands.
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pubmed:publicationType |
Journal Article,
In Vitro,
Research Support, U.S. Gov't, P.H.S.,
Research Support, Non-U.S. Gov't
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