(en) A sliced and orthotopically grafted rat gastrocnemius is able to regenerate thanks to the presence of mononuclear cells. If the mince is inactivated by a freeze-thaw procedure with liquid nitrogen before the autograft, there is no muscle regeneration. We enriched inactivated mince with cells extracted with trypsin from the contralateral muscle in three different ways. 60 days after the operation, the regenerates contained muscle fibers and were contractile. In conclusion, isolated and autografted myoblasts are capable of regenerating contractile muscle tissue.