Journal of Applied Physiology
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

J Appl Physiol 98: 1228-1233, 2005. First published October 29, 2004; doi:10.1152/japplphysiol.00665.2004
8750-7587/05 $8.00
This Article
Right arrow Full Text Free
Right arrow Full Text (PDF) Free
Right arrow All Versions of this Article:
98/4/1228    most recent
00665.2004v1
Right arrow Submit a response
Right arrow Alert me when this article is cited
Right arrow Alert me when eLetters are posted
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in ISI Web of Science
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via ISI Web of Science (3)
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Eijnde, B. O.
Right arrow Articles by Hespel, P.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Eijnde, B. O.
Right arrow Articles by Hespel, P.

AMP kinase expression and activity in human skeletal muscle: effects of immobilization, retraining, and creatine supplementation

Bert O. Eijnde,1 Wim Derave,1 Jørgen F. P. Wojtaszewski,2 Erik A. Richter,2 and Peter Hespel1

1Exercise Physiology and Biomechanics Laboratory, Department of Kinesiology, Faculty of Kinesiology and Rehabilitation Sciences, Katholieke Universiteit Leuven, Leuven, Belgium; and 2Copenhagen Muscle Research Centre, Institute of Exercise and Sports Sciences, University of Copenhagen, Copenhagen, Denmark

Submitted 25 June 2004 ; accepted in final form 26 October 2004

The effects of leg immobilization and retraining in combination with oral creatine intake on muscle AMP-activated protein kinase (AMPK) protein expression and phosphorylation status were investigated. A double-blind trial was performed in young healthy volunteers (n = 22). A cast immobilized the right leg for 2 wk, whereafter the knee-extensor muscles of that leg were retrained for 6 wk. Half of the subjects received creatine monohydrate throughout the study (Cr; from 15 g down to 2.5 g daily), and the others ingested placebo (P; maltodextrin). Before and after immobilization and retraining, needle biopsies were taken from the right and left vastus lateralis muscles. In the right leg of P and Cr, immobilization did not affect AMPK {alpha}1-, {alpha}2-, and {beta}2-subunit expression or AMPK {alpha}-subunit phosphorylation status. However, irrespective of the treatment received, retraining increased the degree of {alpha}-subunit phosphorylation by ~25% (P < 0.05) and increased AMPK {alpha}1-subunit expression (P < 0.05) in both groups. From the start to the end of the study, AMPK subunit protein expression and {alpha}-subunit phosphorylation status were unchanged in the contralateral control leg. It is concluded that immobilization-induced muscle inactivity for 2 wk does not alter AMPK {alpha}1-, {alpha}2-, and {beta}2-subunit expression or {alpha}-AMPK phosphorylation status. Furthermore, the present observations indicate that AMPK probably is not implicated in the previously reported beneficial effects of oral creatine supplementation on muscle during immobilization and rehabilitative weight training.

training; AMP-activated protein kinase


Address for reprint requests and other correspondence: B. O. Eijnde, Exercise Physiology and Biomechanics Laboratory, Faculty of Kinesiology and Rehabilitation Sciences, Tervuursevest 101, B-3001 Leuven, Belgium (E-mail: Bert.OpTEijnde{at}faber.kuleuven.be)






HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Visit Other APS Journals Online
Copyright © 2005 by the American Physiological Society.