[The facilitatory effect of sympathetic efferents on sustained discharges of polymodal nociceptors].
Injection of a compound algogenic substance into receptive field of the skin induced sustained discharges of polymodal nociceptors in rats. The sustained discharges were obviously increased by stimulation of the sympathetic nerve innervating the receptive field. Initial facilitation was followed by the inhibition of discharges in partial units. The sympathetic effect can be activated repeatedly and lasted for a prolonged time. Injection of norepinephrine (5 micrograms/0.2 ml) into the local artery could cause the similar effect. Results indicate that the sympathetic efferents facilitates the sustained discharges of polymodal nociceptors. The possibility of producing causalgia and contrary results of experiments were discussed.
Hu
S J
SJ
Zhu
J
J
D000818:Animals; D004525:Efferent Pathways / Q000502:physiology; D004594:Electrophysiology; D008297:Male; D009619:Nociceptors / Q000502:physiology*; D009638:Norepinephrine / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D013564:Sympathetic Nervous System / Q000502:physiology*
D009638:Norepinephrine