Articles : The Expression of Myogenic growth Factor in Skeletal Muscle by Endurance Training

Journal of Exercise Nutrition & Biochemistry 2002;6(3):253-258.

Abstract

I
t was the aim of this study to investigate the expression of IGF-Ⅰ mRNA in the different fiber type and contractile property of skeletal muscle by endurance training. The male Sprague-Dawley rats underwent the treadmill running at the 55% of VO2 max (20m/min, 10°, 90min/day, 5days/week) during the 2, 4 and 8 weeks respectively. The expression of IGF-Ⅰ mRNA in gastrocnemius and soleus muscles were examined by quantitative Northern blotting. In the gastrocnemius and soleus IGF-Ⅰ mRNA level were increased after 2 weeks and 4 weeks endurance training and after 8weeks gradually decreased but higher than control group. These results indicate that the high expression of IGF-Ⅰ mRNA by endurance training may be contributing to the hypertrophy and regeneration response via the mobilization of satellite cells to provide increases in muscle DNA.

Key Words: Endurance training, IGF-I mRNA, Gastrocnemius, Soleus