Autografted minced muscle fragments do not affect muscle regeneration in partially excised rat gastrocnemius muscle

The kinetics of the regeneration process following partial excision or mincing in the rat gastrocnemius muscle was compared using histological and physiological methods. Immediately following injury there was a marked decrease in the distance of shortening (DS) values during isotonic contraction, followed by a progressive increase until 2 weeks after injury. By 85 days the DS values attained those of control muscle during contraction against low loads (up to 50 g), and 80 and 62% of control values at 150 and 250 g, respectively. However. there was no difference in the DS values at 28 and 85 days after injury between muscles that were partially excised or when the removed part of the muscle was minced and placed in the injured site. It is concluded that the enrichment of an injured area of the gastrocnemius muscle with minced autografted muscle does not result in long-term improvement of the functional capacity of the regenerated muscle due to the addition of satellite cells and/or other factors in the minced tissue.