Linked Life Data

11001769

Source:http://linkedlifedata.com/resource/pubmed/id/11001769

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
2000-10-12
pubmed:abstractText
Previous studies have indicated that frequency of stimulation is a major determinant of glucose transport in contracting muscle. We have now studied whether this is so also when total force development or metabolic rate is kept constant. Incubated soleus muscles were electrically stimulated to perform repeated tetanic contractions at four different frequencies (0.25, 0.5, 1, and 2 Hz) for 10 min. Resting length was adjusted to achieve identical total force development or metabolic rate (glycogen depletion and lactate accumulation). Overall, at constant total force development, glucose transport (2-deoxyglucose uptake) increased with stimulation frequency (P < 0.05; basal: 25 +/- 2, 0.25 Hz: 50 +/- 4, 0.5 Hz: 50 +/- 3, 1 Hz: 81 +/- 5, 2 Hz: 79 +/- 3 nmol. g(-1). 5 min(-1)). However, glucose transport was identical (P > 0.05) at the two lower (0.25 and 0.5 Hz) as well as at the two higher (1 and 2 Hz) frequencies. Glycogen decreased (P < 0.05; basal: 19 +/- 1, 0.25 Hz: 13 +/- 1, 0.5 Hz: 12 +/- 2, 1 Hz: 7 +/- 1, 2 Hz: 7 +/- 1 mmol/kg) and 5'-AMP-activated protein kinase (AMPK) activity increased (P < 0. 05; basal: 1.7 +/- 0.4, 0.25 Hz: 32.4 +/- 7.0, 0.5 Hz: 36.5 +/- 2.1, 1 Hz: 63.4 +/- 8.0, 2 Hz: 67.0 +/- 13.4 pmol. mg(-1). min(-1)) when glucose transport increased. Experiments with constant metabolic rate were carried out in soleus, flexor digitorum brevis, and epitrochlearis muscles. In all muscles, glucose transport was identical at 0.5 and 2 Hz (P > 0.05); also, AMPK activity did not increase with stimulation frequency. In conclusion, muscle glucose transport increases with stimulation frequency but only in the face of energy depletion and increase in AMPK activity. This indicates that contraction-induced glucose transport is elicited by metabolic demands rather than by events occurring early during the excitation-contraction coupling.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0193-1849
pubmed:author
pubmed:issnType
Print
pubmed:volume
279
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
E862-7
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:11001769-Adenosine Diphosphate, pubmed-meshheading:11001769-Adenosine Monophosphate, pubmed-meshheading:11001769-Adenosine Triphosphate, pubmed-meshheading:11001769-Adenylate Kinase, pubmed-meshheading:11001769-Animals, pubmed-meshheading:11001769-Biological Transport, pubmed-meshheading:11001769-Deoxyglucose, pubmed-meshheading:11001769-Electric Stimulation, pubmed-meshheading:11001769-Glucose, pubmed-meshheading:11001769-Glycogen, pubmed-meshheading:11001769-Inosine Monophosphate, pubmed-meshheading:11001769-Lactic Acid, pubmed-meshheading:11001769-Male, pubmed-meshheading:11001769-Muscle, Skeletal, pubmed-meshheading:11001769-Muscle Contraction, pubmed-meshheading:11001769-Phosphocreatine, pubmed-meshheading:11001769-Rats, pubmed-meshheading:11001769-Rats, Wistar, pubmed-meshheading:11001769-Reaction Time
pubmed:year
2000
pubmed:articleTitle
Effect of stimulation frequency on contraction-induced glucose transport in rat skeletal muscle.
pubmed:affiliation
Copenhagen Muscle Research Centre, University of Copenhagen, 2200 Copenhagen N, Denmark. jihlemann@mfi.ku.dk
pubmed:publicationType
Journal Article, In Vitro, Research Support, Non-U.S. Gov't