Evaluation of gene expression through qRT-PCR in cyclically loaded tendons: an in vivo model.
Asundi-KR; King-KB; Rempel-DM
Eur J Appl Physiol 2008 Mar; 102(3):265-270
An in vivo rabbit animal model for the tendinopathy, epicondylitis, was used to examine the effects of repetitive load on the expression of various genes associated with matrix remodeling. Following 80 h of cumulative load, tissue from the distal and proximal regions of the flexor digitorum profundus tendon was collected. Quantitative RT-PCR was used to asses mRNA levels of collagenase-1 (MMP-1), stromelysin (MMP-3), vascular endothelial growth factor (VEGF), connective tissue growth factor (CTGF), cyclooxygenase-2 (COX-2), interleukin-1ß (IL-1ß), type III collagen (COL-III) and fibronectin (FBRN). No significant differences in expression levels were found between loaded and unloaded limbs at either region of the tendon. The findings were unexpected as the same model has already demonstrated an increase in the density of cells staining for VEGF and CTGF. Different regulatory mechanisms between mRNA and protein expression or localized changes missed due to homogenization of the tissue samples, may explain the discrepancy in findings.
Biological-effects; Biological-function; Biomechanical-engineering; Biomechanical-modeling; Biomechanics; Cell-biology; Cellular-reactions; Cumulative-trauma; Cumulative-trauma-disorders; Ergonomics; Exposure-assessment; Exposure-levels; Exposure-methods; Genetic-factors; Laboratory-testing; Mechanics; Musculoskeletal-system; Musculoskeletal-system-disorders; Neurological-reactions; Physiological-effects; Physiological-measurements; Physiological-response; Quantitative-analysis; Repetitive-work; Risk-analysis; Risk-factors; Tissue-disorders; Tissue-distribution;
Author Keywords: Overuse injury; Quantitative RT-PCR; Vascular endothelial growth factor; Connective tissue growth factor
D. M. Rempel, Ergonomics Program, 1301 South 46th Street, Building 163, Richmond, CA 94804
European Journal of Applied Physiology
University of California, Berkeley