Hideto Okazaki, MD, PhD, Hidehiko Beppu, MT, PhD, Kenmei Mizutani, MT, PhD,
Shigeru Sonoda, MD, PhD
Jpn J Compr Rehabil Sci 4: 84-87, 2013
Purpose: Hepatocyte growth factor (HGF) contributes
to the proliferation of muscle cells, however, the
relationship between the level of HGF in muscle and
that in the blood is unknown. In this study, we
examined the influence of exercise on HGF levels in
muscle and blood using a rat model of hindlimb
muscle atrophy.
Methods: Thirty female Sprague-Dawley rats were
used. Fifteen of the rats were cast-immobilized for 14
days (CAS); the remaining fifteen rats were allowed
normal activity as the control group (CNT). After
removal of the cast, rats were divided into three groups
(n=5 per group) as follows: a pre-exercise group (PE),
a normal activity group (normal activity for seven
days) (NA) and a treadmill training group (20° slope,
15 m per min, 20 min per day for seven days; TR). The
CNT group was also divided into the same three
groups. At the end of the study period, the wet weight
of the left soleus muscle per body weight, plasma HGF
level and left soleus muscle HGF level were measured
and multiple comparisons were performed.
Results: Muscle weight was significantly lower in
CAS-PE than in all CNT groups. Muscle HGF level
was significantly higher in CAS-TR than in either
CAS-PE or CAS-NA. There were no statistically
significant differences between any of the other
groups.
Conclusion: Muscle HGF is expressed in response to
relatively high intensity exercise but the dynamics of
HGF are limited to intramuscular distribution.
Key words: atrophy, exercise, HGF