HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Free Full Text (PDF) Free Supplementary Figure All Versions of this Article: 101/1/151    most recent 00392.2005v1 Submit a response Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via ISI Web of Science (9) Citing Articles via Google Scholar Google Scholar Articles by Iemitsu, M. Articles by Miyauchi, T. Search for Related Content PubMed PubMed Citation Articles by Iemitsu, M. Articles by Miyauchi, T.

Activation pattern of MAPK signaling in the hearts of trained and untrained rats following a single bout of exercise

¹Institute of Health and Sport Sciences, ²Cardiovascular Division, Institute of Clinical Medicine, and ³Center for Tsukuba Advanced Research Alliance, University of Tsukuba, Tsukuba, Ibaraki; and ⁴Graduate School of Medicine, Chiba University, Inohana, Chiba, Japan

Submitted 8 April 2005 ; accepted in final form 13 February 2006

Since exercise training causes cardiac hypertrophy and a single bout induces mechanical stress to the heart, the present study aimed to characterize the activation patterns of multiple MAPK signaling pathways in the heart after a single bout of exercise or chronic exercises. The hearts of untrained rats received 5, 15, and 30 min of treadmill running exercise (Ex5 to Ex30) and rested for 0.5, 1, 3, 6, 12, and 24 h (PostEx0.5 to PostEx24) before subjecting them to the following different experiments. Activation of MAPKs (ERK, JNK, and p38) and MAPKKs (MEK1/2, SEK, and MKK3/6) increased immediately after acute exercise in a time-dependent manner, with ERK, JNK, and p38 peaking at Ex15, Ex15, and Ex30, respectively. Expression of immediate early genes (c-fos, c-jun, and c-myc) was augmented and activator protein-1 DNA binding activity was enhanced in untrained rats immediately after a single bout of exercise. The elevated levels of MAPKs declined to the resting levels within 24 h after exercise. In another set of experiments, following 4, 8, and 12 wk of exercise training, the rats exhibited significant cardiac hypertrophy by week 12. Activation of MAPKs in the 4-wk-trained rats increased after a 30-min single bout of exercise but decreased in the 8-wk group. Finally, the activity of MAPKs signaling in the 12-wk-trained rats exposed to an acute bout of exercise was unaltered. We conclude that exercise induces the activation of multiple MAPK (ERK, JNK, and p38) pathways in the heart, an effect that gradually declines with the development of exercise-induced cardiac hypertrophy.

cardiac hypertrophy; extracellular signal-regulated kinase; c-Jun NH₂-terminal kinase; p38; treadmill running

This article has been cited by other articles:

				M. Iemitsu, N. Shimojo, S. Maeda, Y. Irukayama-Tomobe, S. Sakai, T. Ohkubo, Y. Tanaka, and T. Miyauchi The benefit of medium-chain triglyceride therapy on the cardiac function of SHRs is associated with a reversal of metabolic and signaling alterations Am J Physiol Heart Circ Physiol, July 1, 2008; 295(1): H136 - H144. [Abstract] [Full Text] [PDF]

				D. J. Kosek and M. M. Bamman Modulation of the dystrophin-associated protein complex in response to resistance training in young and older men J Appl Physiol, May 1, 2008; 104(5): 1476 - 1484. [Abstract] [Full Text] [PDF]

				M. K. Trenerry, K. A. Carey, A. C. Ward, and D. Cameron-Smith STAT3 signaling is activated in human skeletal muscle following acute resistance exercise J Appl Physiol, April 1, 2007; 102(4): 1483 - 1489. [Abstract] [Full Text] [PDF]

				S. Jesmin, S. Zaedi, N. Shimojo, M. Iemitsu, K. Masuzawa, N. Yamaguchi, C. N. Mowa, S. Maeda, Y. Hattori, and T. Miyauchi Endothelin antagonism normalizes VEGF signaling and cardiac function in STZ-induced diabetic rat hearts Am J Physiol Endocrinol Metab, April 1, 2007; 292(4): E1030 - E1040. [Abstract] [Full Text] [PDF]