Abstract: Objective To observe the alterations in soleus nerve conduction velocities induced by hindlimb immobilization. Methods 24 healthy Sprague-Dawley rats were randomly divided into control group, immobilization 7 days group and immobilization 14 days group with 8 cases in each group. The plaster cast was fixed as the method to induce a hindllimb immobilization model in rats. The afferent thin fibers conduction velocity and the latency of M wave were observed with electrophysiological technique. Results 7 days after immobilization,the conduction velocity of muscle spindle primary afferent fiber decreased (P<0.05), the latency of M wave significantly prolonged 14 days after immobilization (P<0.05). Conclusion The soleus nerve conduction velocities decrease significantly following hindlimb immobilization and the alterations in afferent fibers are more serious than that in efferent fibers.

Key words: immobilization, skeletal muscle, conduction velocity, rats