Cardiopulmonary sympathetic afferent input does not require dorsal column pathways to excite C1-C3 spinal cells in rats.
Effects of electrically stimulating the left stellate ganglion to activate cardiopulmonary sympathetic afferent (CPSA) fibers were determined on C1-C3 dorsal horn neurons in anaesthetized rats. Fifty-two of 53 dorsal horn neurons affected by CPSA stimulation were excited and one neuron was inhibited. In 6 experiments, dorsal columns and ventrolateral funiculi were sequentially lesioned to determine neuronal pathways involved in CPSA activation of C1-C3 neurons. In 6 additional experiments, spinal transection at rostral C1 was used to determine the contribution of supraspinal relays. We concluded that CPSA input to C1-C3 segments travelled bilaterally in ventrolateral pathways, and that supraspinal relays were not required for CPSA excitation of C1-C3 neurons. These results suggest that neurons in C1-C3 segments might play an important role in processing visceral spinal afferent information.
Zhang
J
J
Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City 73190, USA.
Chandler
M J
MJ
Miller
K E
KE
Foreman
R D
RD
D000344:Afferent Pathways / Q000502:physiology*; D000818:Animals; D004558:Electric Stimulation; D006321:Heart / Q000294:innervation*; D008168:Lung / Q000294:innervation*; D008297:Male; D009412:Nerve Fibers / Q000502:physiology; D009474:Neurons / Q000502:physiology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013116:Spinal Cord / Q000502:physiology*; D013233:Stellate Ganglion / Q000502:physiology*; D013564:Sympathetic Nervous System / Q000502:physiology