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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
2
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pubmed:dateCreated |
1988-4-21
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pubmed:abstractText |
Cholesteryl ester-rich beta-very low density lipoproteins (beta-VLDL) are beta-migrating lipoproteins that accumulate in the plasma of cholesterol-fed animals and of patients with type III hyperlipoproteinemia. There are two distinct fractions: fraction I beta-VLDL are chylomicron remnants of intestinal origin, and fraction II beta-VLDL are cholesterol-rich VLDL of hepatic origin. The liver rapidly clears fraction I beta-VLDL from the plasma of both normal and cholesterol-fed dogs. The liver also clears fraction II beta-VLDL rapidly and efficiently from the plasma of normal dogs by receptor-mediated uptake. In cholesterol-fed dogs the clearance is biphasic: an initial rapid die-away of about 30% to 40% of the injected dose within 5 minutes, followed by a slow clearance of plasma radioactivity (a half-life of more than 20 hours). The rapid, initial phase of fraction II beta-VLDL clearance appears to be related to sequestration of the lipoproteins presumably on endothelial cells and is apparently associated with lipolytic processing. Treatment of the fraction II beta-VLDL with lipoprotein lipase abolishes this rapid phase. In the cholesterol-fed dog, the slow, late phase of clearance corresponds to the conversion of fraction II beta-VLDL to the smaller, denser intermediate and low density lipoproteins (IDL and LDL), which are slowly cleared from the plasma. It is concluded that fraction II beta-VLDL are catabolized in the normal dog by rapid uptake mediated at least in part by the apo B,E(LDL) receptor of hepatic parenchymal cells. In cholesterol-fed dogs, in which these receptors are markedly down-regulated, fraction II beta-VLDL are apparently initially bound to endothelial cells and converted to IDL and LDL by lipolytic processing.
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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/Cholesterol, Dietary,
http://linkedlifedata.com/resource/pubmed/chemical/Lipoproteins, VLDL,
http://linkedlifedata.com/resource/pubmed/chemical/Receptors, Cell Surface,
http://linkedlifedata.com/resource/pubmed/chemical/Receptors, Lipoprotein,
http://linkedlifedata.com/resource/pubmed/chemical/apolipoprotein B,E receptor,
http://linkedlifedata.com/resource/pubmed/chemical/chylomicron receptor
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pubmed:status |
MEDLINE
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pubmed:issn |
0276-5047
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pubmed:author | |
pubmed:issnType |
Print
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pubmed:volume |
8
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
130-9
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pubmed:dateRevised |
2003-11-14
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pubmed:meshHeading |
pubmed-meshheading:2831863-Animals,
pubmed-meshheading:2831863-Cholesterol, Dietary,
pubmed-meshheading:2831863-Dogs,
pubmed-meshheading:2831863-Lipoproteins, VLDL,
pubmed-meshheading:2831863-Liver,
pubmed-meshheading:2831863-Male,
pubmed-meshheading:2831863-Receptors, Cell Surface,
pubmed-meshheading:2831863-Receptors, Lipoprotein
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pubmed:articleTitle |
Metabolism of canine beta-very low density lipoproteins in normal and cholesterol-fed dogs.
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pubmed:affiliation |
Department of Pathology, University of California, San Francisco.
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pubmed:publicationType |
Journal Article
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