title: Effects of phosphodiesterase type 5 inhibitor, tadalafil, on continence reflex in rats.
abstract: OBJECTIVE
  Effects of tadalafil, a phosphodiesterase type 5 inhibitor, on the urethral continence reflex induced by sneezing were investigated.
  
  
  METHODS
  The amplitude of urethral pressure responses during sneezing (A-URS) and urethral baseline pressure (UBP) were measured in female rats using a microtransducer-tipped catheter. Sneeze leak-point pressure (S-LPP), defined as the lowest amount of pressure required to induce fluid leakage from the urethral orifice during sneezing, was measured in rats with stress urinary incontinence (SUI) induced by vaginal distension. Values were determined before and after tadalafil administration.
  
  
  RESULTS
  Tadalafil dose dependently and significantly decreased A-URS and S-LPP. At the highest dose tested (6.0 mg/kg), A-URS and S-LPP decreased from 49.7 to 32.3 and from 63.9 to 44.2 cmH2O, respectively, whereas UBP did not significantly change.
  
  
  CONCLUSIONS
  Tadalafil attenuated the sneeze-induced urethral continence reflex by relaxing the striated muscles of the external urethral sphincter.
authors.affiliation: Department of Urology, Tohoku University Graduate School of Medicine, 1-1 Seiryomachi, Aoba-ku, Sendai, 980-8574, Japan.
authors.forename: Hideaki
authors.initials: H
authors.lastname: Izumi
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Kaiho
authors.forename: Minoru
authors.initials: M
authors.lastname: Miyazato
authors.forename: Naoki
authors.initials: N
authors.lastname: Kawamorita
authors.forename: Haruo
authors.initials: H
authors.lastname: Nakagawa
authors.forename: Yoichi
authors.initials: Y
authors.lastname: Arai
mesh_terms: D000818:Animals; D002243:Carbolines / Q000494:pharmacology / Q000627:therapeutic use*; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D005260:Female; D009126:Muscle Relaxation / Q000187:drug effects / Q000502:physiology; D009130:Muscle, Smooth / Q000187:drug effects / Q000503:physiopathology; D058986:Phosphodiesterase 5 Inhibitors / Q000494:pharmacology / Q000627:therapeutic use*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012018:Reflex / Q000187:drug effects / Q000502:physiology; D000068581:Tadalafil; D016896:Treatment Outcome; D014521:Urethra / Q000187:drug effects / Q000503:physiopathology; D014522:Urethral Diseases / Q000188:drug therapy* / Q000503:physiopathology*; D014550:Urinary Incontinence, Stress / Q000188:drug therapy* / Q000503:physiopathology*
chemical_list: D002243:Carbolines; D058986:Phosphodiesterase 5 Inhibitors; D000068581:Tadalafil