Linked Life Data

2645788

Source:http://linkedlifedata.com/resource/pubmed/id/2645788

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2 Pt 1
pubmed:dateCreated
1989-3-29
pubmed:abstractText
To elucidate the relative roles of insulin (I) and amino acid (AA) availability on body protein economy and AA kinetics, we compared whole body leucine kinetic responses, using a 360-min constant infusion of L-[1-13C]leucine, during administration of an L-AA solution to six healthy young (21-25 yr) and six healthy old (72-87 yr) men (study 1) to those when the AA solution was given in conjunction with a euglycemic I clamp (study 2). In study 1, serum I increased significantly (P less than 0.02) by 4 +/- 1 and 4 +/- 2 microU/ml in young (Y) and old (O) men, respectively. In study 2, I was raised to 91 +/- 7 (Y) and 88 +/- 7 (O) microU/ml; the glucose infusion to maintain euglycemia in the Y was significantly greater than in the O (8.0 +/- 0.1 vs. 6.8 +/- 1.9 mg.kg-1.min-1). Leucine flux and oxidation increased significantly in both age groups during the administration of AA. Estimates of leucine released from protein breakdown declined (P less than 0.01) by 18 and 20% in study 1 and 2, respectively, in the young and by 12 and 44%, respectively, in the elderly. Rates of leucine incorporation into protein increased (P less than 0.01) similarly in both age groups and in both studies. These findings emphasize the importance of AA availability in the stimulation of protein synthesis and suggest that insulin's major role in vivo is to repress whole body proteolysis. Furthermore, despite evidence of an age-related decline in glucose disposal, the elderly had similar leucine kinetic responses to hyperaminoacidemia.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0002-9513
pubmed:author
pubmed:issnType
Print
pubmed:volume
256
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
E288-94
pubmed:dateRevised
2011-11-17
pubmed:meshHeading
pubmed:year
1989
pubmed:articleTitle
Leucine metabolism in aging humans: effect of insulin and substrate availability.
pubmed:affiliation
Department of Applied Biological Sciences, Massachusetts Institute of Technology, Cambridge 02139.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S.