Linked Life Data

9078532

Source:http://linkedlifedata.com/resource/pubmed/id/9078532

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1997-7-1
pubmed:abstractText
Studies in humans and animals indicate that peripheral insulin sensitivity is decreased after puberty. Although glucose, after its uptake and phosphorylation, will be diverted to either the glycolytic or glycogen synthesis pathway, these pathways have not been characterized after the transition to puberty. Thus, we examined the changes in the pathways of glucose utilization in conscious (n = 22) prepuberty (81 +/- 3 g), and postpuberty (258 +/- 9 g) Sprague-Dawley rats. Insulin stimulated (by insulin clamp 18 mU/kg/min) glucose uptake [rate of glucose disappearance (Rd)] was decreased by approximately 30% postpuberty (from 339 +/- 22 to 239 +/- 28 mumol/kg/min; p < 0.001). Although glycolysis (estimated by the rate of conversion of [3H]glucose to 3H2O) decreased by approximately 15% (p < 0.05), glycogen synthesis decreased by approximately 40% (from 200 +/- 17 prepuberty to 122 +/- 22 mumol/kg/min postpuberty; p < 0.001), and accounted for approximately 80% of the decrease in Rd postpuberty. Decrease in the capacity to store glycogen in response to insulin was also confirmed by approximately 40% decrease in both glycogen levels, and in 3H accumulation into glycogen (from 3H-glucose) at the end of the clamp study. This occurred in the absence of any changes in either the K(m) or the Vmax of glycogen synthase nor in the activity of glycogen phosphorylase. We conclude that the postpubertal decrease in insulin responsiveness is characterized by decreased ability to store muscle glycogen. We propose that high capacity for muscle glycogen synthesis may be required to sustain the increased metabolic requirements during peripubertal growth.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0031-3998
pubmed:author
pubmed:issnType
Print
pubmed:volume
41
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
340-5
pubmed:dateRevised
2011-11-17
pubmed:meshHeading
pubmed:year
1997
pubmed:articleTitle
Intracellular pathways of insulin-mediated glucose uptake before and after puberty in conscious rats.
pubmed:affiliation
Division of Adult Endocrinology, Albert Einstein College of Medicine, Bronx, New York 10461, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't