title: Distribution of vanilloid receptors in the rat laryngeal innervation.
abstract: OBJECTIVE
  Capsaicin is known to selectively activate nociceptic sensory neurons through vanilloid receptors. In this study we investigated the distribution of vanilloid receptor subtype 1 (VR1) and vanilloid receptor-like protein 1 (VRL-1) in the rat larynx.
  
  
  METHODS
  The distributions of VR1 and VRL-1 were determined immunohistochemically. The colocalization of vanilloid receptors with common choline acetyltransferase (cChAT), vasoactive intestinal polypeptide (VIP), substance P (SP) and neuronal nitric oxide synthase (nNOS) was also studied using an immunohistochemical double-labeling technique.
  
  
  RESULTS
  VRL-1-positive fibers were detected in the laryngeal epithelium and lamina propria. VR1-positive nerve fibers were seen in the lamina propria but not in the mucosal epithelium. VR1- and VRL-1-positive cells were distributed in the intralaryngeal ganglia and colocalization of capsaicin receptors with VIP, nNOS and cChAT was seen.
  
  
  CONCLUSIONS
  These findings suggest that these capsaicin receptors participate in the parasympathetic innervation as well as in nociception of the rat larynx.
authors.affiliation: Department of Otolaryngology, Kyoto Prefectural University of Medicine, Kyoto, Japan.
authors.forename: Shinobu
authors.initials: S
authors.lastname: Koike
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Uno
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Bamba
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Shibata
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Okano
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Hisa
mesh_terms: D000818:Animals; D002211:Capsaicin / Q000378:metabolism; D007150:Immunohistochemistry; D007473:Ion Channels; D007820:Laryngeal Mucosa / Q000294:innervation; D007823:Laryngeal Nerves / Q000378:metabolism*; D009412:Nerve Fibers / Q000378:metabolism; D009619:Nociceptors / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D011955:Receptors, Drug / Q000378:metabolism*; D050916:TRPV Cation Channels
chemical_list: D007473:Ion Channels; D011955:Receptors, Drug; D050916:TRPV Cation Channels; C494484:TRPV1 receptor; C476722:Trpv2 protein, rat; D002211:Capsaicin