Regeneration and differentiation of minced anterior tibial muscle explants from mice with MED myopathy.

Rapid regeneration of mouse anterior tibial muscle occurs when minced muscle is explanted into the leg of a recipient previously prepared by excision of the corresponding anterior tibial muscle. This technique was used to study regeneration of muscle from mice with a delayed, recessive myopathy, motor endplate disease (MED). There was rapid regeneration of the explanted muscle and functional restoration after 15 weeks without signs of MED disease or evidence of the myofiber degeneration which normally occurs after 14 days in homozygous animals. Therefore, MED disease is not intrinsic in the affected muscles but appears to be dependent on the general humoral or possibly neural, environment present in mice with MED disease.