Collagen and fibronectin in a healing skeletal muscle injury. An immunohistological study of the effects of physical activity on the repair of injured gastrocnemius muscle in the rat

Abstract

The presence of the connective tissue components fibronectin and the different types of collagen was demonstrated by histological and immunohistological methods in the granulation and scar tissue of a healing injury in rat muscle. The effects of physical activity on granulation tissue production, scar formation and muscle regeneration at various stages of healing were studied. It was shown that immobilisation after injury accelerates granulation tissue production, but if continued too long, leads to contraction of the scar and to poor structural organisation of the components of regenerating muscle and scar tissue. However, a certain period of immobilisation, about five days for rat muscle, is required to allow newly-formed granulation tissue to cover the injured area and to have sufficient tensile strength to withstand subsequent mobilisation. This mobilisation, at the correct interval, seems essential for the quicker resorption of scar tissue and the better structural organisation of the muscle.

Growth factors improve muscle healing in vivo

“…3 At the same time, fibroblasts invade the gap and begin to produce extracellular matrix to restore the framework of the connective tissue. 4,5 The physiological role of this scaffold is to transmit load across the defect so that the injured limb can be used before the repair process is complete. 2 In extensive muscle injury, the proliferation of fibroblasts can quickly lead to an excessive formation of dense scar tissue, which impedes regeneration of the muscle and results in an incomplete recovery.…”

A plea for hamstrings early rehabilitation after hamstrings knee plasty

“…Lors des phases de reconstruction cellulaire et de remodelage, à partir du cinquième jour, il stimule la maturation des cellules satellites de Mauro et facilite également l'alignement des myoblastes en myotubes, ainsi que la maturation des myotubes en myofibrilles puis en fibres musculaires selon l'axe de traction [36][37][38][39].…”

Major fibrillar collagens and fibronectin in an experimental nonunion: An immunohistochemical study

“…Fibronectin anchors the matrix components and is thought to have a significant role in the differentiation of mesenchymal cells to chondral cells. It has also been observed to play an important role in granulation tissue formation during wound healing and muscle injury repair (Lehto et al 1985, Mikisalo et al 1989. Immunostaining for collagen I11 was observed not only in the fibrous fracture gap, but also in the newly formed callus tissue, suggesting an active role of osteoblasts participating in the production of collagen I11 in the nonunion.…”

“…For collagen 11, a rabbit antibovine antibody was used (Biodesign@). Antisera against types I11 and V collagen were raised in rabbits and antibodies were prepared by using the immunization schedule previously described (Lehto et al 1985). The color reaction was produced with 0.03% 3.3-diaminobenzidine tetrachloride.…”