|
|
||||||||
1 Department of Kinesiology, 2 School of Pharmacy, 3 Center for Neuroscience, 4 Molecular and Environmental Toxicology Center, and 5 Waisman Center, University of Wisconsin, Madison, Wisconsin 53706
Previous studies have
shown that endurance exercise training increases myocardial
contractility. We have previously described training-induced
alterations in myocardial contractile function at the cellular level,
including an increase in the Ca2+ sensitivity of tension.
To determine the molecular mechanism(s) of these changes,
oligonucleotide microarrays were used to analyze the gene expression
profile in ventricles from endurance-trained rats. We used an 11-wk
treadmill training protocol that we have previously shown results in
increased contractility in cardiac myocytes. After the training, the
hearts were removed and RNA was isolated from the ventricles of nine
trained and nine control rats. With the use of an Affymetrix Rat Genome
U34A Array, we detected altered expression of 27 genes. Several genes
previously found to have increased expression in hypertrophied
myocardium, such as atrial natriuretic factor and skeletal
-actin,
were decreased with training in this study. From the standpoint of
altered contractile performance, the most significant finding was an
increase in the expression of atrial myosin light chain 1 (aMLC-1) in
the trained ventricular tissue. We confirmed microarray results for
aMLC-1 using RT-PCR and also confirmed a training-induced increase in aMLC-1 protein using two-dimensional gel electrophoresis. aMLC-1 content has been previously shown to be increased in human cardiac hypertrophy and has been associated with increased Ca2+
sensitivity of tension and increased power output. These results suggest that increased expression of aMLC-1 in response to training may
be responsible, at least in part, for previously observed training-induced enhancement of contractile function.
atrial natriuretic factor; myosin regulatory light chain; calcium sensitivity
This article has been cited by other articles:
![]() |
J. A. Hill and E. N. Olson Cardiac Plasticity N. Engl. J. Med., March 27, 2008; 358(13): 1370 - 1380. [Full Text] [PDF] |
||||
![]() |
O. M. Hernandez, M. Jones, G. Guzman, and D. Szczesna-Cordary Myosin essential light chain in health and disease Am J Physiol Heart Circ Physiol, April 1, 2007; 292(4): H1643 - H1654. [Abstract] [Full Text] [PDF] |
||||
![]() |
O. Cazorla, Y. Ait Mou, L. Goret, G. Vassort, M. Dauzat, A. Lacampagne, S. Tanguy, and P. Obert Effects of high-altitude exercise training on contractile function of rat skinned cardiomyocyte Cardiovasc Res, September 1, 2006; 71(4): 652 - 660. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. C. Hinken, F. S. Korte, and K. S. McDonald Porcine cardiac myocyte power output is increased after chronic exercise training J Appl Physiol, July 1, 2006; 101(1): 40 - 46. [Abstract] [Full Text] [PDF] |
||||
![]() |
G. Yona, W. Dirks, S. Rahman, and D. M. Lin Effective similarity measures for expression profiles Bioinformatics, July 1, 2006; 22(13): 1616 - 1622. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. W. Starnes, A. M. Choilawala, R. P. Taylor, M. J. Nelson, and M. D. Delp Myocardial Heat Shock Protein 70 Expression in Young and Old Rats After Identical Exercise Programs J. Gerontol. A Biol. Sci. Med. Sci., August 1, 2005; 60(8): 963 - 969. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. De Acetis, A. Notte, F. Accornero, G. Selvetella, M. Brancaccio, C. Vecchione, M. Sbroggio, F. Collino, B. Pacchioni, G. Lanfranchi, et al. Cardiac Overexpression of Melusin Protects From Dilated Cardiomyopathy Due to Long-Standing Pressure Overload Circ. Res., May 27, 2005; 96(10): 1087 - 1094. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. W. Kong, N. Bodyak, P. Yue, Z. Liu, J. Brown, S. Izumo, and P. M. Kang Genetic expression profiles during physiological and pathological cardiac hypertrophy and heart failure in rats Physiol Genomics, March 21, 2005; 21(1): 34 - 42. [Abstract] [Full Text] [PDF] |
||||
![]() |
N. Frey, H. A. Katus, E. N. Olson, and J. A. Hill Hypertrophy of the Heart: A New Therapeutic Target? Circulation, April 6, 2004; 109(13): 1580 - 1589. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. L. Lennon, J. Quindry, K. L. Hamilton, J. French, J. Staib, J. L. Mehta, and S. K. Powers Loss of exercise-induced cardioprotection after cessation of exercise J Appl Physiol, April 1, 2004; 96(4): 1299 - 1305. [Abstract] [Full Text] [PDF] |
||||
![]() |
G. M. Diffee and D. F. Nagle Regional differences in effects of exercise training on contractile and biochemical properties of rat cardiac myocytes J Appl Physiol, July 1, 2003; 95(1): 35 - 42. [Abstract] [Full Text] [PDF] |
||||
![]() |
G. M. Diffee and E. Chung Altered single cell force-velocity and power properties in exercise-trained rat myocardium J Appl Physiol, May 1, 2003; 94(5): 1941 - 1948. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |