title: Swimming: effects on stress urinary incontinence and the expression of nerve growth factor in rats following transabdominal urethrolysis.
abstract: OBJECTIVE
  Stress urinary incontinence (SUI) commonly occurs in women, and it has an enormous impact on quality of life. Surgery, drugs, and exercise have been recommended for the treatment of this disease. Among these, exercise is known to be effective for the relief of symptoms of SUI; however, the efficacy and underlying mechanisms of the effect of exercise on SUI are poorly understood. We investigated the effect of swimming the symptom of SUI in relation to the expression of nerve growth factor (NGF) in rats.
  
  
  METHODS
  Transabdominal urethrolysis was used to induce SUI, in Sprague-Dawley rats. The experimental groups were divided into the following three groups: sham-operation group, transabdominal urethrolysis-induced group, and transabdominal urethrolysis-induced and swimming group. The rats in the swimming group were forced to swim for 30 minutes once daily starting 2 weeks after SUI induction and continuing for 4 weeks. For this study, determination of abdominal leak point pressure and immunohistochemistry for NGF in the urethra and in the neuronal voiding centers (medial preoptic nucleus [MPA], ventrolateral periaqueductal gray [vlPAG], pontine micturition center [PMC], and spinal cord [L4-L5]) were performed.
  
  
  RESULTS
  Transabdominal urethrolysis significantly reduced the abdominal leak point pressure, thereby contributing to the induction of SUI. Abdominal leak point pressure, however, was significantly improved by swimming. The expression of NGF in the urethra and in the neuronal voiding centers (MPA, vlPAG, PMC, and L4-L5) relating to micturition was enhanced by the induction of SUI. Swimming, however, significantly suppressed SUI-induced NGF expression.
  
  
  CONCLUSIONS
  Swimming alleviated symptoms of transabdominal urethrolysis-induced SUI, as assessed by an increase in abdominal leak point pressure. The underlying mechanisms of these effects of swimming might be ascribed to the inhibitory effect of swimming on NGF expression.
authors.affiliation: Department of Physiology, Kyung Hee University School of Medicine, Seoul, Korea.
authors.forename: Il Gyu
authors.initials: IG
authors.lastname: Ko
authors.forename: Sung Eun
authors.initials: SE
authors.lastname: Kim
authors.forename: Bo Kyun
authors.initials: BK
authors.lastname: Kim
authors.forename: Mal Soon
authors.initials: MS
authors.lastname: Shin
authors.forename: Chang Ju
authors.initials: CJ
authors.lastname: Kim
authors.forename: Sung Jin
authors.initials: SJ
authors.lastname: Yim
authors.forename: Yu Jeong
authors.initials: YJ
authors.lastname: Bang
authors.forename: In Ho
authors.initials: IH
authors.lastname: Choi
authors.forename: Khae Hawn
authors.initials: KH
authors.lastname: Kim