Journal of Applied Physiology Ad Instruments
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH
QUICK SEARCH:   [advanced]


     

J Appl Physiol (February 28, 2008). doi:10.1152/japplphysiol.01282.2007
This Article
Right arrow Full Text (PDF) Free
Right arrow All Versions of this Article:
104/5/1366    most recent
01282.2007v1
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
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
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 HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Raney, M. A.
Right arrow Articles by Turcotte, L. P.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Raney, M. A.
Right arrow Articles by Turcotte, L. P.
Submitted on December 5, 2007
Accepted on February 27, 2008

Evidence for the involvement of CaMKII and AMPK in Ca2+-dependent signaling pathways regulating FA uptake and oxidation in contracting rodent muscle

Marcella A. Raney1 and Lorraine P. Turcotte1*

1 Kinesiology, University of Southern California, Los Angeles, California, United States

* To whom correspondence should be addressed. E-mail: turcotte{at}usc.edu.

Calcium-calmodulin/dependent protein kinase II (CaMKII), AMP-activated protein kinase (AMPK), and extracellular signal-regulated kinase (ERK1/2) have each been implicated in the regulation of substrate metabolism during exercise. The purpose of this study was to determine whether CaMKII is involved in the regulation of FA uptake and oxidation and if it is involved, whether it does so independently of AMPK and ERK1/2. Rat hindquarters were perfused at rest with (n=16) or without (n=10) 3 mM caffeine or during electrical stimulation (n=14). For each condition, rats were subdiveded and treated with either 10 µM KN92 or KN93, inactive and active CaMKII inhibitors respectively. Both caffeine treatment and electrical stimulation significantly increased FA uptake and oxidation (P<0.05). KN93 abolished caffeine-induced FA uptake, decreased contraction-induced FA uptake by 33%, and abolished both caffeine- and contraction-induced FA oxidation (P<0.05). Caffeine had no effect on ERK1/2 phosphorylation (P>0.05) and increased {alpha}2-AMPK activity by 68% (P<0.05). Electrical stimulation increased ERK1/2 phosphorylation and {alpha}2-AMPK activity by 51% and 3.4-fold respectively (P<0.05). KN93 had no effect on caffeine-induced {alpha}2-AMPK activity or ERK1/2 phosphorylation or contraction-induced ERK1/2 phosphorylation (P>0.05). Alternatively, it decreased contraction-induced {alpha}2-AMPK activity by 51% (P<0.05) suggesting that CaMKII lies upstream of AMPK. These results demonstrate that regulation of contraction-induced FA uptake and oxidation occurs in part via Ca2+-independent activation of ERK1/2 as well as Ca2+-dependent activation of CaMKII and AMPK.




This article has been cited by other articles:


Home page
 Am. J. Physiol. Regul. Integr. Comp. Physiol.Home page
M. J. Abbott, A. M. Edelman, and L. P. Turcotte
CaMKK is an upstream signal of AMP-activated protein kinase in regulation of substrate metabolism in contracting skeletal muscle
Am J Physiol Regulatory Integrative Comp Physiol, December 1, 2009; 297(6): R1724 - R1732.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Endocrinol. Metab.Home page
B. Egan and J. R. Zierath
Hunting for the SNARK in metabolic disease
Am J Physiol Endocrinol Metab, May 1, 2009; 296(5): E969 - E972.
[Full Text] [PDF]

Home page
 Am. J. Physiol. Endocrinol. Metab.Home page
N. Lefort, E. St.-Amand, S. Morasse, C. H. Cote, and A. Marette
The {alpha}-subunit of AMPK is essential for submaximal contraction-mediated glucose transport in skeletal muscle in vitro
Am J Physiol Endocrinol Metab, December 1, 2008; 295(6): E1447 - E1454.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Endocrinol. Metab.Home page
J. A. H. Smith, T. A. Kohn, A. K. Chetty, and E. O. Ojuka
CaMK activation during exercise is required for histone hyperacetylation and MEF2A binding at the MEF2 site on the Glut4 gene
Am J Physiol Endocrinol Metab, September 1, 2008; 295(3): E698 - E704.
[Abstract] [Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH
Visit Other APS Journals Online
Copyright © 1948 by the American Physiological Society.