title: Differential effects of trigeminal tractotomy on Adelta- and C-fiber-mediated nociceptive responses.
abstract: In this study we have tested in the rat, whether trigeminal tractotomy, which deprives the spinal trigeminal nucleus caudalis (Sp5C) of its trigeminal inputs, affected differentially nociceptive responses mediated by C- vs. Adelta-nociceptors from oral and perioral regions. Tractotomy had no effect on the threshold of the jaw opening reflex, induced by incisive pulp stimulation (Adelta-fiber-mediated), but blocked the formalin response (mainly C-fiber-mediated). These results suggest that nociceptive responses mediated by trigeminal C-fibers completely depend on the integrity of the Sp5C, while intraoral sensations triggered Adelta-fibers (especially of dental origin) are primarily processed in the rostral part of the spinal trigeminal nucleus.
authors.affiliation: Laboratoire de Physiologie Oro-Faciale, Faculté de Chirurgie Dentaire, 11 Bd Charles de Gaulle, 63000, Clermont-Ferrand, France.
authors.forename: J
authors.initials: J
authors.lastname: Pajot
authors.forename: T
authors.initials: T
authors.lastname: Pelissier
authors.forename: F
authors.initials: F
authors.lastname: Sierralta
authors.forename: P
authors.initials: P
authors.lastname: Raboisson
authors.forename: R
authors.initials: R
authors.lastname: Dallel
mesh_terms: D000344:Afferent Pathways / Q000473:pathology / Q000503:physiopathology* / Q000601:surgery*; D000818:Animals; D003714:Denervation / Q000009:adverse effects*; D008297:Male; D009410:Nerve Degeneration / Q000473:pathology / Q000503:physiopathology; D009412:Nerve Fibers / Q000473:pathology* / Q000502:physiology*; D009413:Nerve Fibers, Myelinated / Q000473:pathology* / Q000502:physiology*; D009619:Nociceptors / Q000473:pathology / Q000503:physiopathology* / Q000601:surgery*; D010146:Pain / Q000503:physiopathology* / Q000601:surgery*; D051381:Rats; D017207:Rats, Sprague-Dawley; D014275:Trigeminal Caudal Nucleus / Q000473:pathology / Q000503:physiopathology* / Q000601:surgery*