Effect of One Session Resistance Exercise on mRNA Expression of NT4/5 and P75 Proteins in Slow and Fast Skeletal Muscles of Wistar Rats

Background and Activity-dependent expression of neurotrophins in skeletal muscle is not well established. In this research we aimed at studying the effect of one session resistance exercise on mRNA expression of NT4.5 and P75 proteins in slow and fast skeletal muscles of Wistar rats. Sixteen male Wistar rats (10 wk of age) were housed at room temperature under a controlled light/dark (12-h) cycle with ad libitum access to food and water. They were randomly divided into two groups (resistance exercise (T) and control (C); n=8 in each group). The resistance training protocol consisted climbing a 1-meter–long ladder, with a weight attached to a tail sleeve. For NT-4.5 and P75 expressions, quantitative real time RT-PCR was used. For data analysis the independent-samples t-test was used in SPSS. The level of significance was set at P<0.05. This study showed that resistance exercise significantly decreased mRNA expression of NT4.5 in soleus muscle (P= 0.003). However, no significant alteration was detected in Flexor Hallucis Longus (FHL) muscle (P= 0.743). Our results also indicated that resistance exercise significantly increased mRNA expression of P75 in soleus muscle (P= 0.043). However, this increase was not found in FHL muscle (P= 0.417). One session resistance training altered the mRNA expression of NT4/5 and P75 receptor in soleus muscle. This alteration indicated that probably muscle-derived neurotrophin release plays a key role for exercise-induced adaptation in skeletal muscle.