Volume 87, Issue 2 , Pages 241-246, February 2006
The Effect of 30 Minutes of Passive Stretch of the Rat Soleus Muscle on the Myogenic Differentiation, Myostatin, and Atrogin-1 Gene Expressions
Abstract
Gomes AR, Soares AG, Peviani S, Nascimento RB, Moriscot AS, Salvini TF. The effect of 30 minutes of passive stretch of the rat soleus muscle on the myogenic differentiation, myostatin, and atrogin-1 gene expressions.
Objective
To evaluate the effect of passive stretch, applied for 30 minutes to the rat soleus muscle, on the myogenic differentiation (myoD), myostatin, and atrogin-1 gene expressions.
Design
Case-controlled study.
Setting
University laboratory.
Animals
Fifty 12-week-old male Wistar rats.
Interventions
Six groups of animals were given a single stretch bout and were evaluated immediately and 8, 24, 48, 72, and 168 hours later. Another 3 groups were evaluated immediately after 2, 3, and 7 stretches. An intact control group was also analyzed.
Main Outcome Measures
The messenger ribonucleic acid (mRNA) levels of myoD, myostatin, and atrogin-1 were assessed by real-time polymerase chain reaction.
Results
Twenty-four hours after a single session of stretch only, the myoD mRNA levels had increased compared with the control group, whereas an increase in the atrogin-1 expression was observed after 2, 3, and 7 stretches.
Conclusions
A single session of passive stretch increased the myoD gene expression, a factor related to muscle growth. Interestingly, daily stretches increased the atrogin-1 gene expression, a gene primarily associated with muscle atrophy. The results indicated that gene expression was responsive to the number of stretch sessions.
Key Words: Atrogin-1 , Rats , Muscles , MyoD protein , Stretch , Rehabilitation
Supported by the Fundação de Amparo à Pesquisa do Estado de São Paulo (grant nos. 01/13523-4, 01/135221-1, 03/10889-3), Coordenção de Aperfeiçoamento de Pessoal de Nivel Superior (grant no. 33001014016P7), and Conselho Nacional de Desenvolvimento Científico e Tecnológico (grant no. 501737/2004-9).No commercial party having a direct financial interest in the results of the research supporting this article has or will confer a benefit upon the authors or upon any organization with which the authors are associated.
PII: S0003-9993(05)01194-9
doi:10.1016/j.apmr.2005.08.126
© 2006 American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.
Volume 87, Issue 2 , Pages 241-246, February 2006
