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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
5
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pubmed:dateCreated |
1991-10-21
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pubmed:abstractText |
The effects of aging on the hepatic metabolism of cholesterol were studied in 1-, 6- and 24-month-old male Sprague-Dawley rats. Microsomal 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase activity, which regulates cholesterol biosynthesis, decreased from 835 +/- 144 (SEM) pmol/min/mg protein in the youngest group to 219 +/- 34 and 205 +/- 53 pmol/min/mg protein (p less than 0.001) in the 6- and 24-month-old groups, respectively. Cholesterol 7 alpha-hydroxylase activity, which governs bile acid synthesis, was gradually reduced from 70 +/- 14 pmol/min/mg protein in the 1-month-old group to 32 +/- 7 and 16 +/- 3 pmol/min/mg protein (p less than 0.05) in the 6- and 24-month-old groups, respectively. Acyl coenzyme A:cholesterol acyltransferase activity, which catalyzes the esterification of cholesterol, averaged 431 +/- 47 and 452 +/- 48 pmol/min/mg protein in the 1- and 6-month-old groups, respectively, and was increased to 585 +/- 55 pmol/min/mg protein (p less than 0.05) in the 24-month-old group. The level of total cholesterol showed an age-related increase from 1.56 +/- 0.16 mg/g liver in the 1-month-old group to 1.70 +/- 0.15 and 2.20 +/- 0.19 mg/g liver (p less than 0.05) in the 6- and 24-month-old groups, respectively. The increase was mainly caused by an accumulation of esterified cholesterol. We conclude that a marked decrease in HMG-CoA reductase occurs between 1 and 6 months of age; thereafter the enzyme activity stays unchanged. The activity of cholesterol 7 alpha-hydroxylase decreases progressively and drastically with age, whereas the capacity for esterifying cholesterol increases slightly.(ABSTRACT TRUNCATED AT 250 WORDS)
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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,
http://linkedlifedata.com/resource/pubmed/chemical/Cholesterol 7-alpha-Hydroxylase,
http://linkedlifedata.com/resource/pubmed/chemical/Cholesterol Esters,
http://linkedlifedata.com/resource/pubmed/chemical/Hydroxymethylglutaryl CoA Reductases,
http://linkedlifedata.com/resource/pubmed/chemical/Sterol O-Acyltransferase
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pubmed:status |
MEDLINE
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pubmed:month |
May
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pubmed:issn |
0024-4201
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pubmed:author | |
pubmed:issnType |
Print
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pubmed:volume |
26
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
349-52
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pubmed:dateRevised |
2006-11-15
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pubmed:meshHeading |
pubmed-meshheading:1895880-Aging,
pubmed-meshheading:1895880-Animals,
pubmed-meshheading:1895880-Body Weight,
pubmed-meshheading:1895880-Cholesterol,
pubmed-meshheading:1895880-Cholesterol 7-alpha-Hydroxylase,
pubmed-meshheading:1895880-Cholesterol Esters,
pubmed-meshheading:1895880-Hydroxymethylglutaryl CoA Reductases,
pubmed-meshheading:1895880-Liver,
pubmed-meshheading:1895880-Male,
pubmed-meshheading:1895880-Microsomes, Liver,
pubmed-meshheading:1895880-Organ Size,
pubmed-meshheading:1895880-Rats,
pubmed-meshheading:1895880-Rats, Inbred Strains,
pubmed-meshheading:1895880-Sterol O-Acyltransferase
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pubmed:year |
1991
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pubmed:articleTitle |
Age-related changes in the metabolism of cholesterol in rat liver microsomes.
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pubmed:affiliation |
Department of Medicine, Karolinska Institutet, Huddinge University Hospital, Stockholm, Sweden.
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pubmed:publicationType |
Journal Article,
Comparative Study,
Research Support, Non-U.S. Gov't
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