@article{oai:kanazawa-u.repo.nii.ac.jp:00016844,
 author = {Yagishita, Masafumi},
 issue = {2},
 journal = {金沢大学十全医学会雑誌 = Journal of the Jûzen Medical Society},
 month = {Jun},
 note = {Recently, clinical studies have suggested that eccentric exercise can be beneficial for patellar tendinopathy. It is known that loading induces collagen synthesis in tendon, but the mechanisms responsible for mediating this effect are still unclear. We hypothesized that loading-induced expression of collagen depends on a specific contraction type. Eccentric exercise induces a more beneficial healing response than concentric exercise. Two longitudinal incisions were made in rat patellar tendons and the rats were then divided into three groups: eccentric exercise group (group E; n=35); concentric exercise group (group C; n=35); non-exercise group (group N; n=35). Each rat was taught to run downhill (eccentric) or uphill (concentric) for 14 days. Patellar tendons were collected at 1, 4, 7, 14, 21, 28 and 42 days following injury. Type I and III collagen, transforming growth factor-β-1 (TGF-β-1), and matrix metalloproteinase-13 (MMP-13) were measured by reverse transcription polymerase chain reaction. The gene expression level of type I collagen of group E was significantly greater than that of group N on day 4. The gene expression level of type III collagen of group E was significantly greater than that of group N on days 7 and 14. The gene expression level of TGF-β-1 of group E was significantly greater than that of group C and group N on days 4 and 7. The gene expression level of MMP-13 of group C and group N was significantly greater than that of group E on day 21. Eccentric exercise can more effectively induce TGF- β-1 expression compared to concentric exercise and subsequently cause high expression of type I and III collagen. In addition, our results showed that eccentric exercise also reduces MMP-13 gene expression. In conclusion, eccentric exercise can aid tendon repair., [Originals][原著]平成23年5月18日受付，平成23年6月17日受理},
 pages = {42--49},
 title = {The effect of eccentric exercise on injured patellar tendon healing in rats: a gene expression study},
 volume = {120},
 year = {2011}
}