[Impulse coherent component separation study of spontaneous activity of the splanchnic nerve in chronic experiments...

Spontaneous electrical activity was recorded by a two-channel amplifier from the intact splanchnic nerve of the dog in chronic experiments using the method of coherent recording. In the channel which picked up the action potentials first as they propagated, all pulses were delayed for the time interval which the action potentials needed to reach the other channel. Then the pulses from both channels entered a coincidence unit which counted only the simultaneous pulses from both channels. It is found that spontaneous active afferent fibres had 3.7-20 m/s conduction velocities. At the maximum frequency of the coincident oscillations the average conduction velocity was 9.2 +/- 1.0 m/s. When feeding meat to the dog the second group of active afferent fibres was detected. The average conduction velocity in this group was 5.8 +/- 0.7 m/s with a range of 3.7 - 9.2 m/s. The conduction velocities in the efferent fibres ranged from 2.5 to 9.7 m/s and their mean conduction velocity was 3.5 +/- 0.5 m/s.