Early electrophysiological changes after denervation of slow skeletal muscle

Abstract

Denervation of the soleus muscle was performed on rabbits; the tibial nerve being sectioned at the level of the knee and thigh. Nerve action potentials monitored in the distal nerve stumps indicated functional failure occurred at 66 and 72 hours for knee and thigh sectioned nerve, respectively. The nature of neuronal failure in the tibial nerve was similar to that seen in the peroneal nerve (preceding report) in that failure was simultaneous down the entire length of the axon. However, the relationship between the length of nerve stump and time of failure differed in the tibial nerve as compared to the peroneal. It was also found that the following denervation of the soleus, at two levels on the tibial nerve, produced a loss in tetanic response at the same point in time. These latter findings are contrary to the findings in the anterior tibialis where loss of neuromuscular function was influenced by the level at which denervation was performed.