(1.School of Physical Education,Shangqiu Normal College,Shangqiu 476000,China;2.School of Physical Education,Soochow University,Suzhou 215021,China) Abstract: In order to probed into the mechanism of α7β1 integrin working on the repeated bout effect by observing the changing of the expression of α7β1 integrin and FAK as well as FAK activity after downhill running, the authors divided 32 mice randomly into a calm control group, a 3 h after running group, a 24 h after running group, and an 8d after running group, let the mice carry out one-time downhill running at a speed of 17 m/min, on a slope of -20°, for 30 minutes, took the eyeball blood and both-sides gastrocnemius of the mice in various groups at the said times, measured serum CK activity by means of colorimetry, measured the mRNA expression of α7β1 integrin and FAK by means of real-time PCR, measured the protein expression of α7β1 integrin and pFAK397 by means of Western blot, and revealed the following findings: after one-time downhill running, CK activity increased significantly, and the increment increased at 24 h; α7 integrin mRNA increased significantly at 3 h after one-time running, but changed insignificantly at 24 h, yet still increased significantly on day 8, its protein level increased significantly at 3 h after running, the degree of increasing was still significantly although it decreased gradually at 24 h and on day 8; β1 in-tegrin mRNA increased significantly at 3 h after one-time running, changed insignificantly at 24 h and on day 8, its protein level increased significantly at 3 h after one-time running, the degree of increasing increased at 24 h, but dropped back on day 8; FAK mRNA increased significantly at 3 h after one-time running, changed insignificantly at 24 h and on day 8, pFAK397 level increased significantly after one-time running, the degree of increasing decreased at 24 h, basically dropped back on day 8. The said findings indicate that α7β1 integrin and FAK signal pathway me-diated the repeated bout effect. Key words: exercise biochemistry;downhill running;skeletal muscle;integrin;FAK;repeated bout effect;mouse |