Source
Department of Orthodontics and Oral Biology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands.
Abstract
PURPOSE:
The purpose of this study was to establish an in vivo model for muscle regeneration after strain injury in the presence of a fibrotic discontinuity.
METHODS:
The musculus soleus of 5-wk-old male rats was exposed, completely lacerated, and sutured together with or without a collagen scaffold in between the muscle ends. The scaffold represents a fibrotic discontinuity in the muscle. Muscle healing was evaluated after 14 d by general histology and staining for myofibroblasts, satellite cells (activated), and inflammatory cells.
RESULTS:
Around all wounds, satellite cells were activated. Inside the collagen scaffolds, satellite cells were absent, indicating that muscle regeneration was impaired. In the wounds without a collagen scaffold, the lacerated and the sutured myofibers contacted and had already started to regenerate, whereas this did not occur with an implanted scaffold.
CONCLUSIONS:
A fibrotic discontinuity, such as an implanted collagen scaffold, delays muscle regeneration in skeletal muscle. This model is suitable to study skeletal muscle regeneration in the presence of a fibrotic lesion and to evaluate new treatment modalities for muscle strain injuries.