MyoD, Myogenin and Myosin Heavy Chain mRNA Expression in Rat Skeletal Muscle after a Single Session of Low-Intensity Treadmill Exercise

Myogenic cell response to muscle contraction with short electrical stimulation

[Purpose] The present study aimed to determine the effects of short muscle strength exercise on hepatocyte growth factor expression and satellite cell activation. [Subjects] The study included 72 2-12-week-old male Sprague-Dawley rats. [Methods] The rat plantaris muscle was contracted with a 5-min electrical stimulation of the sciatic nerve, and then, the mRNA expressions of hepatocyte growth factor and myogenic regulatory factors in the plantaris muscle were determined, and the phosphorylation of the hepatocyte growth factor receptor (c-Met) was examined. [Results] The mRNA expressions of hepatocyte growth factor and myogenic regulatory factors increased after a short muscle contraction compared to that un-contraction. Immunofluorescence analysis showed the expression of hepatocyte growth factor protein and the possibility that downstream biological changes occurred in the hepatocyte growth factor-bound c-Met. [Conclusion] Our results demonstrated that activation of satellite cells induced hepatocyte growth factor expression during muscle contraction with a short 5-min electrical stimulation, which simulates short muscle strength exercise in physical therapy. The present study provides evidence for the use of short muscle strength exercise in physical therapy.