title: The role of transient receptor potential ankyrin 1 (TRPA1) channel in activation of single unit mechanosensitive bladder afferent activities in the rat.
abstract: OBJECTIVE
  We investigated the role of transient receptor potential ankyrin 1 (TRPA1) channel on the single unit mechanosensitive afferent activities (SAAs) primarily originating from the bladder in the rat.
  
  
  METHODS
  Female Sprague-Dawley rats were used. Cystometry with continuous saline instillation was performed after intra-venous cumulative administration of HC-030031 (HC, a selective TRPA1 antagonist) at three doses (0.1, 1.0, and 10.0 mg/kg) in conscious rats. SAAs primarily originating from the bladder were identified by electrical stimulation of the pelvic nerve and by bladder distention, and divided by conduction velocity as Aδ- or C-fibers under urethane anesthesia. The SAA-investigation was repeated three times with cumulative HC-administration at three doses (0.1, 1.0, and 10.0 mg/kg) or single administration of vehicle. In separate experiments, the SAA-investigation was repeated three times with intra-vesical instillation of allyl isothiocyanate (AI, a TRPA1 agonist, 10 µM) or vehicle with or without pretreatment with HC (1.0 mg/kg, 3 min before each intra-vesical instillation of AI).
  
  
  RESULTS
  There was no significant change in any cystometric parameters after HC-administrations. A total of 54 SAAs (25 Aδ-fibers and 29 C-fibers) was isolated in 28 rats. SAAs of both fibers significantly decreased after HC-administrations in a dose-dependent manner. SAAs of both fibers significantly increased after AI-instillations. Pretreatment with HC suppressed this excitatory effect of AI-instillation on SAAs.
  
  
  CONCLUSIONS
  TRPA1 channel has a role in activation of mechanosensitive afferent nerve activities of both Aδ- and C-fibers of the rat bladder, although its role in a physiological condition might be small. Neurourol. Urodynam. 33:544-549, 2014. © 2013 Wiley Periodicals, Inc.
authors.affiliation: Faculty of Medicine, Department of Urology, Antwerp University Hospital and University of Antwerp, Antwerp, Wilrijk, Belgium.
authors.forename: Tomonori
authors.initials: T
authors.lastname: Minagawa
authors.forename: Naoki
authors.initials: N
authors.lastname: Aizawa
authors.forename: Yasuhiko
authors.initials: Y
authors.lastname: Igawa
authors.forename: Jean-Jacques
authors.initials: JJ
authors.lastname: Wyndaele
mesh_terms: D000083:Acetanilides; D000818:Animals; D005260:Female; D040542:Mechanotransduction, Cellular; D009413:Nerve Fibers, Myelinated / Q000502:physiology*; D036421:Nerve Fibers, Unmyelinated / Q000502:physiology*; D009475:Neurons, Afferent / Q000502:physiology*; D011687:Purines; D051381:Rats; D017207:Rats, Sprague-Dawley; D000074025:TRPA1 Cation Channel; D050052:TRPC Cation Channels / Q000502:physiology*; D001743:Urinary Bladder / Q000294:innervation* / Q000502:physiology
chemical_list: C552888:2-(1,3-dimethyl-2,6-dioxo-1,2,3,6-tetrahydro-7H-purin-7-yl)-N-(4-isopropylphenyl)acetamide; D000083:Acetanilides; D011687:Purines; D000074025:TRPA1 Cation Channel; D050052:TRPC Cation Channels; C480976:Trpa1 protein, rat
keywords: HC-030031; afferent nerves; allyl isothiocyanate; transient receptor potential ankyrin 1; urinary bladder