کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
4074635 1267016 2014 8 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Age-related changes affect rat rotator cuff muscle function
ترجمه فارسی عنوان
تغییرات مرتبط با سن، عملکرد عضلات روتاتور کاف را بررسی می کنند
موضوعات مرتبط
علوم پزشکی و سلامت پزشکی و دندانپزشکی ارتوپدی، پزشکی ورزشی و توانبخشی
چکیده انگلیسی

BackgroundThe influence of age on rotator cuff function and muscle structure remains poorly understood. We hypothesize that normal aging influences rotator cuff function, muscle structure, and regulatory protein expression in an established rat model of aging.MethodsSeventeen rats were obtained from the National Institute on Aging. The supraspinatus muscles in 11 middle-aged (12 months old) and 6 old (28 months old) rats were studied for age-related changes in rotator cuff neuromuscular function by in vivo muscle force testing and electromyography (EMG). Changes in muscle structure and molecular changes were assessed with quantitative immunohistochemistry for myogenic determination factor 1 (MyoD) and myogenic factor 5 (Myf5) expression.ResultsOld animals revealed significantly decreased peak tetanic muscle force at 0.5 N and 0.7 N preload tension (P < .05). The age of the animal accounted for 20.9% of variance and significantly influenced muscle force (P = .026). Preload tension significantly influenced muscle force production (P < .001) and accounted for 12.7% of total variance. There was regional heterogeneity in maximal compound motor action potential (CMAP) amplitude in the supraspinatus muscle; the proximal portion had a significantly higher CMAP than the middle and distal portions (P < .05). The expression of muscle regulatory factors MyoD and Myf5 was significantly decreased in old animals compared with middle-aged animals (P < .05).ConclusionsThe normal aging process in this rat model significantly influenced contractile strength of the supraspinatus muscle and led to decreased expression of muscle regulatory factors. High preload tensions led to a significant decrease in force production in both middle-aged and old animals.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Shoulder and Elbow Surgery - Volume 23, Issue 1, January 2014, Pages 91–98
نویسندگان
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