Voluntary resistance wheel exercise during post-natal growth in rats enhances skeletal muscle satellite cell and myonuclear content at adulthood.

摘要: Aim:  To determine whether voluntary free wheel (FW) or resistance (RW) exercise reduced muscle activity would influence maturational increases in mass and the number of satellite cells (SCs) myonuclei (MN) accrued by adulthood. Methods:  Hind limb muscles male rats housed with, without, FWs from 4 to 5, 7 10 weeks age, with RWs 10 week were evaluated. assess effect activity, gastrocnemius 4-week-old injected botulinum toxin (Btx) collected at 7 weeks age. Muscle fibre size frequency Pax7-positive SCs MN determined 7- 10-week-old via immunohistochemical methods. Results:  Free enhanced growth medial (MG) (threefold) vastus lateralis (VL) (twofold) Resistance increased (22–30%), more nuclei being associated larger size, soleus, MG VL muscles. Btx impaired normal accrual but not SCs. Conclusion:  A greater volume during was important for enhancing SC numbers, whereas their conversion required higher-intensity exercise. The nuclear populations may capacity adapt exercise, injury disuse later adulthood.