2022 Volume 37 Issue 4 Pages 383-386
[Purpose] This study investigated the effect of aging on muscle regeneration in rats. [Participants and Methods] Male Wistar rats were divided into 3 groups of 10-week-old, 24-week-old, and 95-week-old animals. We administered a cardiotoxin to the soleus of the rats to create a skeletal muscle injury model, and physiological analysis and histological analysis was performed at 1, 2, 4, 7, 14, 28 days after cardiotoxin administration. [Results] The cross-sectional area of the injured skeletal muscle increased over time in all of the groups, but it was observed earlier in the younger groups. The number of Pax7 positive cells peaked in the 10-week-old- and 24-week-old groups on day 4 after cardiotoxin administration, but the peak was delayed in the 95-week-old group. [Conclusion] The results suggest that skeletal muscle hypertrophy and the number of muscle satellite cells expressed decreases with aging.