Response of sensory receptors of the cat's hindlimb to a transient,step-function DC electric field

There are two possible mechanisms of effects of large electric fields on animals, one caused by the electric field at the body surface and the other caused by the electric current induced inside the body. The purpose of the present experiments was to investigate the former possibility by recording action potentials from afferent fibers innervating various sensory receptors in the cat's hindlimb. Cat hairs were attracted to the upper electrode when exposed to DC electric fields of 180 kV/m or greater, and action potentials were evoked in the afferent fibers innervating G₁, G₂, and down hair receptors. No action potentials were evoked in afferent fibers innervating type I, type II, field receptors, muscle spindles, or joint receptors. These results indicate that a strong DC electric field induced movement of the hairs, eventually evoked excitation of the hair receptors, but that other receptors located under the skin were not influenced by electric field exposure.