Increase in substance P in the dorsal horn during a chemogenic nociceptive stimulus.
Substance P has been implicated as a neuromediator of nociception in the dorsal horn of the spinal cord. This is the first report of quantitative increases in substance P following an acute nociceptive stimulus. Female Wistar rats were injected subcutaneously in the plantar aspect of the right hindpaw with 5% formalin. Substance P levels were determined by quantitative immunohistochemistry 1 h after the injection. The present results show that substance P levels in the upper two laminae of the ipsi-and contralateral dorsal horn were significantly increased 1 h after the formalin injection. These results suggest a direct functional relationship between substance P levels in the upper dorsal horn and an acute chemogenic nociceptive stimulus.
R M
RM
Kantner
M L
ML
Kirby
B D
BD
Goldstein
D000818:Animals; D004594:Electrophysiology; D005260:Female; D005557:Formaldehyde / Q000494:pharmacology; D005727:Ganglia, Spinal / Q000502:physiology; D007124:Immunoenzyme Techniques; D009619:Nociceptors / Q000187:drug effects*; D010783:Photometry; D051381:Rats; D011919:Rats, Inbred Strains; D013116:Spinal Cord / Q000378:metabolism*; D013373:Substance P / Q000096:biosynthesis*; D013997:Time Factors
D005557:Formaldehyde; D013373:Substance P