Characteristics of myogenic response and ankle torque recovery after lengthening contraction-induced rat gastrocnemius injury

BMC Musculoskeletal Disorders

Research Article

Kihyuk Lee¹  Kenji Hiranuma¹  Koichi Nakazato¹  Hongsun Song²  Eisuke Ochi³ 

[1] Graduate School of Health and Sport Science, Nippon Sport Science University, 7-1-1, Fukasawa, 158-8508, Setagaya-ku, Tokyo, Japan;Korea Institute of Sport Science, San223-19, Gongneung-2Dong, 139-242, Nowon-gu, Seoul, South Korea;Laboratory of Health and Sports Sciences, Center for Liberal Arts, Meiji Gakuin University, 1518 Kamikurata-cho, 244-8539, Totsuka-ku, Yokohama, Kanagawa, Japan;

关键词: Muscle injury;    Eccentric contraction;    Regeneration;    Myogenic factor;   

DOI  :  10.1186/1471-2474-13-211

 received in 2012-05-21, accepted in 2012-10-22,  发布年份 2012

来源: Springer

【 摘 要 】

BackgroundAlthough muscle dysfunction caused by unfamiliar lengthening contraction is one of most important issues in sports medicine, there is little known about the molecular events on regeneration process. The purpose of this study was to investigate the temporal and spatial expression patterns of myogenin, myoD, pax7, and myostatin after acute lengthening contraction (LC)-induced injury in the rat hindlimb.MethodsWe employed our originally developed device with LC in rat gastrocnemius muscle (n = 24). Male Wistar rats were anesthetized with isoflurane (aspiration rate, 450 ml/min, concentration, 2.0%). The triceps surae muscle of the right hindlimb was then electrically stimulated with forced isokinetic dorsi-flexion (180°/sec and from 0 to 45°). Tissue contents of myoD, myogenin, pax7, myostatin were measured by western blotting and localizations of myoD and pax7 was measured by immunohistochemistry. After measuring isometric tetanic torque, a single bout of LC was performed in vivo.ResultsThe torque was significantly decreased on days 2 and 5 as compared to the pre-treatment value, and recovered by day 7. The content of myoD and pax7 showed significant increases on day 2. Myogenin showed an increase from day 2 to 5. Myostatin on days 5 and 7 were significantly increased. Immunohistochemical analysis showed that myoD-positive/pax7-positive cells increased on day 2, suggesting that activated satellite cells play a role in the destruction and the early recovery phases.ConclusionWe, thus, conclude that myogenic events associate with torque recovery after LC-induced injury.

【 授权许可】

Unknown   
© Song et al.; licensee BioMed Central Ltd. 2012. This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.