title: Effects of mirodenafil, a phosphodiesterase-5 inhibitor, on female rat bladder in a partial bladder outlet obstruction model: physiological and immunohistochemical aspects.
abstract: OBJECTIVE
  We investigated the effects of mirodenafil, a phosphodiesterase-5 inhibitor developed in South Korea, on the female rat bladder in a partial bladder outlet obstruction (BOO) model.
  
  
  METHODS
  Thirty-six female Sprague-Dawley rats were divided into four groups: the control group, BOO without medication group, BOO with mirodenafil 1 mg/kg group, and BOO with mirodenafil 4 mg/kg group. Mirodenafil was administered orally for 2 weeks after the induction of BOO. Two weeks after BOO, the rats in each group underwent cystometry under urethane anesthesia. After cystometry, the bladder was excised to perform immunohistochemical staining for connexin 43.
  
  
  RESULTS
  The three BOO groups showed significant increases in mean bladder weight compared with the control group. Baseline pressure, threshold pressure, and maximum contraction pressure were not significantly different between the four groups. Although the contraction interval was decreased in all BOO groups compared with the control group, it was prolonged in the two groups treated with mirodenafil compared with the untreated BOO group. In the immunohistochemical examination, connexin 43 staining intensity in the lamina propria increased in the three BOO groups compared with the control group. The two groups treated with mirodenafil, however, showed decreased connexin 43 staining compared with the untreated BOO group.
  
  
  CONCLUSIONS
  Mirodenafil may increase the contraction intervals of female rat bladders in a partial BOO model. Decreasing bladder overactivity by mirodenafil may be related to intracellular communication mechanisms involving connexin 43.
authors.affiliation: Department of Urology, Eulji General Hospital, Seoul, Korea.
authors.forename: Jung Yoon
authors.initials: JY
authors.lastname: Kang
authors.forename: Eun Kyung
authors.initials: EK
authors.lastname: Kim
authors.forename: Kwang Myung
authors.initials: KM
authors.lastname: Kim
keywords: Connexin 43; Overactive urinary bladder; Phosphodiesterase inhibitors; Urinary bladder neck obstruction