| Abstract: | Conditioning stimuli were applied to the common peroneal or superficial peroneal nerve in acute experiments on anesthetized cats. Changes in the N1-component of the dorsal cord potential evoked by stimulation of one of these nerves or of other nerves (tibial, deep peroneal) and changes in the amplitude of antidromic action potentials in the afferent fibers of these nerves were investigated. The degree of reinforcement of antidromic action potentials, reflecting the degree of depolarization of the afferent terminals, was found to be greater for the passive nerve than for the active to which the conditioning stimulus was applied. Inhibition of the N1-component of the dorsal cord potential was deeper when a pair of stimuli was applied to two different nerves (under these conditions only the mechanism of presynaptic inhibition was activated) than when they were applied to the same nerve. It is concluded that presynaptic inhibition, by selectively controlling afferent volleys, can evidently play a coordinating role. |
