Spinal projections to the parabrachial nucleus are substance P-immunoreactive.
Substance P plays an important role in nociceptive processing in the spinal cord. Substance P is also present in several supraspinal regions, such as the pontine parabrachial nucleus, a major relay for autonomic regulation. In this study we examined in the cat with an immunogold method the presence of substance P-like immunoreactivity in spinoparabrachial terminals that were labelled by anterograde transport of unconjugated and lectin-conjugated horseradish peroxidase. We found that dense core vesicles in anterogradely labelled terminals were substance P-immunoreactive. Taken together with previous observations that noxious stimuli increase preprotachykinin expression in ascending nociceptive pathways from the spinal dorsal horn, the present finding provides evidence that substance P is involved in nociceptive processing also in the brain stem.
Blomqvist
A
A
Department of Cell Biology, Faculty of Health Sciences, University of Linköping, Sweden.
Mackerlova
L
L
D000344:Afferent Pathways / Q000737:chemistry; D000818:Animals; D002415:Cats; D007150:Immunohistochemistry; D008297:Male; D009411:Nerve Endings / Q000737:chemistry*; D010146:Pain / Q000503:physiopathology*; D011149:Pons / Q000502:physiology*; D013116:Spinal Cord / Q000502:physiology*; D013373:Substance P / Q000032:analysis*
D013373:Substance P