title: Postsynaptic dorsal column pathway of the rat. II. Evidence against an important role in nociception.
abstract: The response characteristics of neurons at the origin of the postsynaptic dorsal column (PSDC) pathway were determined in unanesthetized, decerebrated, spinalized rats. Sixty-four percent of PSDC neurons responded only to innocuous mechanical stimuli. Thirty-six percent responded to innocuous stimuli but were more powerfully activated by noxious pinch. Ninety-three percent of the tested PSDC neurons were not activated by any of several intensities of sustained, repeated noxious heating of their receptive fields. The failure of pinch-responsive PSDC cells to respond to thermal stimulation, even in sensitized skin, suggests that they do not receive a functionally significant input from C polymodal nociceptors, heat nociceptors, or mechanical-heat nociceptors. We conclude, therefore, that the postsynaptic dorsal column pathway is not importantly involved in nociception in the rat.
mesh_terms: D000344:Afferent Pathways / Q000503:physiopathology; D000818:Animals; D001931:Brain Mapping; D003655:Decerebrate State / Q000503:physiopathology; D006358:Hot Temperature; D008297:Male; D008465:Mechanoreceptors / Q000502:physiology; D008526:Medulla Oblongata / Q000503:physiopathology*; D009413:Nerve Fibers, Myelinated / Q000502:physiology; D010146:Pain / Q000503:physiopathology*; D051381:Rats; D013116:Spinal Cord / Q000503:physiopathology*