Low intensity spinal cord stimulation may induce cutaneous vasodilation via CGRP release.
This study examined whether spinal cord stimulation (SCS) at intensities below motor threshold (MT) produces cutaneous vasodilation through sympathetic inhibition and/or antidromic activation of sensory fibers. SCS was applied to anesthetized rats with stimulus parameters used clinically, i.e. 50 Hz, 0.2 ms and stimulus intensities at 30, 60 or 90% of MT. SCS-induced vasodilation was not attenuated by hexamethonium, an autonomic ganglion blocking agent, but was abolished by CGRP-(8-37), an antagonist of the calcitonin gene-related peptide (CGRP) receptor. We concluded that SCS-induced vasodilation under the conditions of this study was mediated by peripheral release of CGRP via antidromic activation of sensory fibers.
Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73190, USA.
S
S
Tanaka
K W
KW
Barron
M J
MJ
Chandler
B
B
Linderoth
R D
RD
Foreman
D000818:Animals; D001794:Blood Pressure / Q000502:physiology; D015740:Calcitonin Gene-Related Peptide / Q000378:metabolism* / Q000494:pharmacology; D004558:Electric Stimulation; D005730:Ganglionic Blockers / Q000494:pharmacology; D006339:Heart Rate / Q000502:physiology; D018738:Hexamethonium / Q000494:pharmacology; D008297:Male; D009475:Neurons, Afferent / Q000378:metabolism; D010446:Peptide Fragments / Q000378:metabolism* / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D012867:Skin / Q000098:blood supply*; D013116:Spinal Cord / Q000502:physiology*; D013564:Sympathetic Nervous System / Q000502:physiology; D014664:Vasodilation / Q000187:drug effects / Q000502:physiology*
D005730:Ganglionic Blockers; D010446:Peptide Fragments; C058636:calcitonin gene-related peptide (8-37); D018738:Hexamethonium; D015740:Calcitonin Gene-Related Peptide