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Background and Objective: Trophic factor family plays a key role for neuromuscular system healthy. This study was carried out to determine the effect of one session of resistance exercise on protein content and mRNA expression of NT4/5 in rat slow and fast muscles. Methods: In this experimental study, sixteen adult male rats randomly were allocated into resistance exercise (T) and control groups. The resistance training protocol consisted of climbing a 1-meter–long ladder, with a weight attached to a tail sleeve. Quantitative Real time RT-PCR for NT-4/5 expression and ELISA Kit for protein assay were used. Results: Resistance training significantly decreased mRNA expression and increased protein of NT4/5 in soleus muscle (P<0.05). Significant alteration was not detected in flexor hallucis longus muscle. Conclusion: One session of resistance training can alter protein and mRNA of NT-4/5 in skeletal muscle and this alteration was dependent on muscle type.

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Background and Objective: Skeletal muscle expresses several neurotrophin and their receptors which providing the basis for neurotrophin signaling within the muscle compartments. This study was done to evaluate the effect of a session of resistance exercise on mRNA expression of NT-3 and TrkC proteins in soleus muscle of Wistar Rats. Methods: In this experimental study, 16 male Wistar rats were randomly allocated into exercise and control groups. The resistance training protocol consisted of climbing a 1-meter–long ladder, with a weight attached to a tail sleeve. Expressions of NT-4/5 and P75, quantitatively were measured using RT-PCR. Results: There was not any significant alteration in NT-3 mRNA in soleus muscle after resistance exercise. However, one session of resistance exercise significantly increased mRNA expression of TrkC (1.7 Folds) in soleus muscle (P<0.05). Conclusion: Resistance exercise increases TrkC expression in soleuse muscle of wistar rats.