Response of mef2 Gene of Slow and Fast Twitch Muscles of Wistar Male Rats to One Bout of Resistance Exercise

Myocyte Enhancer Factor 2 (mef2) gene relates with multiple myogenic transcriptional factors that induces activation Muscle-specific genes. MEF2 contributes in muscular cells development and differentiation as well as in fibers transition in response to stimulants. Therefore, the aim of this study was to evaluate the effect of one bout of resistance exercise (RE) on mef2 gene expression in fast and slow skeletal muscles of Wistar male rats.
For this experimental study, 15 rats from Pasteur Institute were prepared and housed under natural conditions (temperature, light/dark (12:12) cycle, with ad libitum access to food and water) and then randomly divided assigned to RE (n=10) and control groups (n=5); the RE group performed one RE session. 3 and 6 hours following, the rats were anaesthetized and sacrificed, then the soleus and Extensor digitorum longus (EDL) muscles were removed. determine mef2 gene expression rate, the Quantitative Real time RT-PCR was used. Data were analyzed by one sample and independent samples t test.
In EDL muscle, in response to one RE session, the mef2 gene expression increased non significantly at 3 hour (p=0/093) and increased significantly (p=/008) at 6 hour after exercise, but in soleus muscle, the mef2 gene expression decreased significantly at 3 hour (p=0/01), and at 6 hour after RE session there was no observed significant change (p=0.247).
Mef2 expression gene is differently changes in muscle fibers, which are likely associated with changes in fiber type in response to resistance exercise.