| Control of exercise-stimulated muscle glucose uptake by GLUT4 is dependent on glucose phosphorylation capacity in the conscious mouse. | |
| | |
MedLine Citation:
|
PMID: 15456776 Owner: NLM Status: MEDLINE |
Abstract/OtherAbstract:
|
Previous work suggests that normal GLUT4 content is sufficient for increases in muscle glucose uptake (MGU) during exercise because GLUT4 overexpression does not increase exercise-stimulated MGU. Instead of glucose transport, glucose phosphorylation is a primary limitation of exercise-stimulated MGU. It was hypothesized that a partial ablation of GLUT4 would not impair exercise-stimulated MGU when glucose phosphorylation capacity is normal but would do so when glucose phosphorylation capacity was increased. Thus, C57BL/6J mice with hexokinase II (HKII) overexpression (HK(Tg)), a GLUT4 partial knock-out (G4(+/-)), or both (HK(Tg) + G4(+/-)) and wild-type (WT) littermates were implanted with carotid artery and jugular vein catheters for sampling and infusions at 4 months of age. After a 7-day recovery, 5-h fasted mice remained sedentary or ran on a treadmill at 0.6 mph for 30 min (n = 9-12 per group) and received a bolus of 2-deoxy[3H]glucose to provide an index of MGU (Rg). Arterial blood glucose and plasma insulin concentrations were similar in WT, G4(+/-), HKTg, and HKTg + G4(+/-) mice. Sedentary Rg values were the same in all genotypes in all muscles studied, confirming that glucose transport is a significant barrier to basal glucose uptake. Gastrocnemius and soleus Rg were greater in exercising compared with sedentary mice in all genotypes. During exercise, G4(+/-) mice had a marked increase in blood glucose that was corrected by the addition of HK II overexpression. Exercise Rg (micromol/100g/min) was not different between WT and G4(+/-) mice in the gastrocnemius (24 +/- 5 versus 21 +/- 2) or the soleus (54 +/- 6 versus 70 +/- 7). In contrast, the enhanced exercise Rg observed in HKTg mice compared with that in WT mice was absent in HKTg + G4(+/-) mice in both the gastrocnemius (39 +/- 7 versus 22 +/- 6) and the soleus (98 +/- 13 versus 65 +/- 13). Thus, glucose transport is not a significant barrier to exercise-stimulated MGU despite a 50% reduction in GLUT4 content when glucose phosphorylation capacity is normal. However, when glucose phosphorylation capacity is increased by HK II overexpression, GLUT4 availability becomes a marked limitation to exercise-stimulated MGU. |
| | |
Authors:
|
Patrick T Fueger; Holli S Hess; Kelly A Posey; Deanna P Bracy; R Richard Pencek; Maureen J Charron; David H Wasserman |
Related Documents
:
|
17040946 - Development of computational models for the purpose of conducting individual livestock ... 23478476 - Acute and chronic effects of resistive exercise on blood pressure in hypertensive elder... 1311706 - Non-o1 vibrio cholerae nrt36s produces a polysaccharide capsule that determines colony ... 7726106 - The effect of relative humidity on mouse allergen levels in an environmentally controll... 1753726 - Effects of swimming and land exercises versus swimming and water exercises on body comp... 17197276 - Behavior therapy and cognitive-behavioral therapy of obesity: is there a difference? |
Publication Detail:
|
Type: Journal Article; Research Support, U.S. Gov't, P.H.S. Date: 2004-09-28 |
Journal Detail:
|
Title: The Journal of biological chemistry Volume: 279 ISSN: 0021-9258 ISO Abbreviation: J. Biol. Chem. Publication Date: 2004 Dec |
Date Detail:
|
Created Date: 2004-11-25 Completed Date: 2005-01-11 Revised Date: 2007-11-14 |
Medline Journal Info:
|
Nlm Unique ID: 2985121R Medline TA: J Biol Chem Country: United States |
Other Details:
|
Languages: eng Pagination: 50956-61 Citation Subset: IM |
Affiliation:
|
Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, Tennessee 37232, USA. patrick.fueger@duke.edu |
Export Citation:
|
APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
|
Animals Biological Transport Blood Glucose / metabolism Cell Membrane / metabolism Densitometry Genotype Glucose / metabolism*, pharmacokinetics* Glucose Transporter Type 4 Glycogen / metabolism Heterozygote Hexokinase / metabolism Immunoblotting Insulin / blood Kinetics Male Mice Mice, Inbred C57BL Mice, Knockout Mice, Transgenic Monosaccharide Transport Proteins / metabolism* Muscle Proteins / metabolism* Muscle, Skeletal / metabolism* Muscles / metabolism Phosphorylation Physical Conditioning, Animal Time Factors |
| Grant Support | |
ID/Acronym/Agency:
|
R01 DK-47425/DK/NIDDK NIH HHS; R01 DK-54902/DK/NIDDK NIH HHS; U24 DK-59637/DK/NIDDK NIH HHS |
| Chemical | |
Reg. No./Substance:
|
0/Blood Glucose; 0/Glucose Transporter Type 4; 0/Monosaccharide Transport Proteins; 0/Muscle Proteins; 0/Slc2a4 protein, mouse; 11061-68-0/Insulin; 50-99-7/Glucose; 9005-79-2/Glycogen; EC 2.7.1.1/Hexokinase |
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
Previous Document: Functional characterization of Escherichia coli DNA adenine methyltransferase, a novel target for an...
Next Document: The small GTPase Cdc42 regulates actin polymerization and tension development during contractile sti...