| AMPK activation is not critical in the regulation of muscle FA uptake and oxidation during low-intensity muscle contraction. | |
| | |
MedLine Citation:
|
PMID: 15547141 Owner: NLM Status: MEDLINE |
Abstract/OtherAbstract:
|
To determine the role of AMP-activated protein kinase (AMPK) activation on the regulation of fatty acid (FA) uptake and oxidation, we perfused rat hindquarters with 6 mM glucose, 10 microU/ml insulin, 550 microM palmitate, and [14C]palmitate during rest (R) or electrical stimulation (ES), inducing low-intensity (0.1 Hz) muscle contraction either with or without 2 mM 5-aminoimidazole-4-carboxamide-1-beta-D-ribofuranoside (AICAR). AICAR treatment significantly increased glucose and FA uptake during R (P < 0.05) but had no effect on either variable during ES (P > 0.05). AICAR treatment significantly increased total FA oxidation (P < 0.05) during both R (0.38 +/- 0.11 vs. 0.89 +/- 0.1 nmol x min(-1) x g(-1)) and ES (0.73 +/- 0.11 vs. 2.01 +/- 0.1 nmol x min(-1) x g(-1)), which was paralleled in both conditions by a significant increase and significant decrease in AMPK and acetyl-CoA carboxylase (ACC) activity, respectively (P < 0.05). Low-intensity muscle contraction increased glucose uptake, FA uptake, and total FA oxidation (P < 0.05) despite no change in AMPK (950.5 +/- 35.9 vs. 1,067.7 +/- 58.8 nmol x min(-1) x g(-1)) or ACC (51.2 +/- 6.7 vs. 55.7 +/- 2.0 nmol x min(-1) x g(-1)) activity from R to ES (P > 0.05). When contraction and AICAR treatment were combined, the AICAR-induced increase in AMPK activity (34%) did not account for the synergistic increase in FA oxidation (175%) observed under similar conditions. These results suggest that while AMPK-dependent mechanisms may regulate FA uptake and FA oxidation at rest, AMPK-independent mechanisms predominate during low-intensity muscle contraction. |
| | |
Authors:
|
Marcella A Raney; Alice J Yee; Mark K Todd; Lorraine P Turcotte |
Publication Detail:
|
Type: Journal Article; Research Support, Non-U.S. Gov't; Research Support, U.S. Gov't, P.H.S. Date: 2004-11-16 |
Journal Detail:
|
Title: American journal of physiology. Endocrinology and metabolism Volume: 288 ISSN: 0193-1849 ISO Abbreviation: Am. J. Physiol. Endocrinol. Metab. Publication Date: 2005 Mar |
Date Detail:
|
Created Date: 2005-02-07 Completed Date: 2005-04-26 Revised Date: 2008-11-21 |
Medline Journal Info:
|
Nlm Unique ID: 100901226 Medline TA: Am J Physiol Endocrinol Metab Country: United States |
Other Details:
|
Languages: eng Pagination: E592-8 Citation Subset: IM |
Affiliation:
|
Dept. of Kinesiology and Biological Sciences, Diabetes Research Center, Univ. of Southern California, 3560 Watt Way, PED 107, Los Angeles, CA 90089-0652, USA. |
Export Citation:
|
APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
|
AMP-Activated Protein Kinases Acetyl-CoA Carboxylase / metabolism Aminoimidazole Carboxamide / analogs & derivatives*, pharmacology Animals Electric Stimulation Enzyme Activation Fatty Acids / metabolism*, pharmacokinetics Glucose / metabolism, pharmacology Hypoglycemic Agents / pharmacology Lactic Acid / metabolism, pharmacology Male Malonyl Coenzyme A / metabolism Multienzyme Complexes / metabolism* Muscle Contraction / physiology* Muscle, Skeletal / drug effects, metabolism, physiology* Oxidation-Reduction Oxygen Consumption / physiology Palmitic Acid / metabolism, pharmacology Protein-Serine-Threonine Kinases / metabolism* Rats Rats, Wistar Ribonucleotides / pharmacology |
| Grant Support | |
ID/Acronym/Agency:
|
AR-45168/AR/NIAMS NIH HHS |
| Chemical | |
Reg. No./Substance:
|
0/Fatty Acids; 0/Hypoglycemic Agents; 0/Multienzyme Complexes; 0/Ribonucleotides; 3031-94-5/AICA ribonucleotide; 360-97-4/Aminoimidazole Carboxamide; 50-21-5/Lactic Acid; 50-99-7/Glucose; 524-14-1/Malonyl Coenzyme A; 57-10-3/Palmitic Acid; EC 2.7.11.1/AMP-Activated Protein Kinases; EC 2.7.11.1/Protein-Serine-Threonine Kinases; EC 6.4.1.2/Acetyl-CoA Carboxylase |
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
Previous Document: It takes time to make a pinky: unexpected insights into how SHH patterns vertebrate digits.
Next Document: Involvement of calcium-sensing receptor in osteoblastic differentiation of mouse MC3T3-E1 cells.