Effect of denervation of neonatal rat sciatic nerve on the differentiation of myosin in a single muscle fiber

Abstract Myosin light chains in normal and neonatally denervated rat muscle were studied to examine the neural effect on the differentiation of myosin molecules. Those of fast- or slow-twitch muscle were identified by single fiber gel electrophoresis. Myosin light chains of rat soleus and extensor digitorum longus (EDL) muscles were converted to the fast type after neonatal denervation. In denervated EDL muscle, some hypertrophied intermediate fibers remained even after 30 days. Single fiber gel electrophoresis showed that slow and fast types of myosin light chains coexisted in these hypertrophied fibers.