Effects of electrical stimulation of the dorsal cutaneous branches of spinal nerves on the discharge activity of remote mechanoreceptive units in rats / 生理学报

ABSTRACT

The method of isolating filaments of the dorsal cutaneous branches was used to observe the effects of antidromic electrical stimulation of the spinal nerves on the discharge of remote A delta and C mechanoreceptive units in rats. Seventy-nine mechanoreceptive units were recorded from the T12 nerve filaments after stimulation of the dorsal cutaneous branches of T9 spinal nerve. It was found that the discharge frequency of 59.3% (16/27) A delta-units and 71.2% (37/52) C-units significantly increased during 90-120 s after the stimulation. Sixty-four mechanoreceptive units were recorded from the T12 nerve filaments after stimulation of the dorsal cutaneous branches of T8 spinal nerves. The discharge frequency of 47.8% (11/23) A delta-units and 36.6% (15/41) C-units significantly increased during 120-150 s after the stimulation. In addition, the threshold of the majority of these mechanoreceptors (78.3%, 18/23) decreased after the stimulation. The results suggest that antidromic electrical stimulation of the dorsal cutaneous branches of spinal nerves leads to sensitization of A delta and C mechanoreceptive units of the remote peripheral nerve endings, which results in an increase in afferent discharge of these units.