Physiological properties of sensory fibers in the spinal ventral roots in the cat

Abstract

The physiological properties of afferent impulses which were recorded from the distal cut end of lumbosacral ventral roots of the cat were investigated by applying weak natural stimuli to the hindlimb. These afferent impulses were considered to arise from the sensory fibers originating from aberrant cells in the ventral roots and mixed nerves (beyond the point of dorsal/ventral root separation). Of 29 sensory fibers recorded from the 7 L7, 13 S1 and 1 S22 ventral roots, 6 fibers were from muscle spindle, 8 fibers innervated the skin, 7 fibers responded to joint movement, 1 fiber showed discharges associated with movement of the experimental table and 1 fiber responded to both mechanical and temperature stimulation. The receptive fields of 6 fibers were not determined by the stimulus modalities employed. The properties of the sensory receptors which are innervated by these aberrant sensory fibers were similar to those innervated by the dorsal root afferent fibers. © 1971, PHYSIOLOGICAL SOCIETY OF JAPAN. All rights reserved.