Gomes Anna R, Soares Antonio G, Peviani Sabrina, Nascimento Rubia B, Moriscot Anselmo S, Salvini Tania F
Unit of Skeletal Muscle Plasticity, Department of Physical Therapy, Federal University of São Carlos, Brazil.
Arch Phys Med Rehabil. 2006 Feb;87(2):241-6. doi: 10.1016/j.apmr.2005.08.126.
The effect of 30 minutes of passive stretch of the rat soleus muscle on the myogenic differentiation, myostatin, and atrogin-1 gene expressions.
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.
Case-controlled study.
University laboratory.
Fifty 12-week-old male Wistar rats.
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.
The messenger ribonucleic acid (mRNA) levels of myoD, myostatin, and atrogin-1 were assessed by real-time polymerase chain reaction.
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.
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.
