Effect of denervation and injected nerve extract on soluble proteins of extensor digitorum longus muscles of rats

Right extensor digitorum longus muscles of rats were denervated. After 7 days the soluble proteins were extracted from denervated and contralateral control muscles and fractionated into 32 bands by electrophoresis on polyacrylamide gels. The distribution of protein among the bands was calculated for each muscle. In denervated muscles the proportion of the total protein was increased in 11 bands and decreased in 6, relative to control muscles. Daily injection of denervated muscles with nerve extract, previously shown to offset postdenervation loss of muscle protein and shrinkage of muscle fibers, prevented the increased level of one protein and exaggerated the change in two others. Two bands, not affected by denervation, were decreased by the extract.