title: Successful induction of stress urinary incontinence in mice by vaginal distension does not depend on the estrous cycle.
abstract: OBJECTIVE
  To determine if the performance of vaginal distension (VD) in different estrous cycle phases affects the successful induction of stress urinary incontinence in mice.
  
  
  METHODS
  Female virgin C57BL/6 mice were distributed into 4 groups according to their estrous cycle phase: proestrus, estrus, metestrus, or diestrus. The estrous cycle was staged by examining vaginal smears, and the method was corroborated by histologic examination of the vagina in a subset of each group. Each group was divided into 4 subgroups for measurement of 24-hour micturition behavior and the leak point pressure (LPP) 4 or 20 days after VD or sham VD.
  
  
  RESULTS
  Voiding events increased and mean void volume decreased 4 days, but not 20 days after VD, and the LPP was decreased 4 days, but not 20 days after VD compared with the corresponding sham group, regardless of the estrous cycle phase when VD was performed. There were no differences in 24-hour micturition behavior or LPP among the 4 different estrous cycle phases either in sham or VD group.
  
  
  CONCLUSIONS
  Successful induction of reversible stress urinary incontinence in mice is not dependent on the estrous cycle.
authors.affiliation: Urology Institute, University Hospitals Case Medical Center, and Department of Urology, Case Western Reserve University School of Medicine, Cleveland, OH; Department of Urology, The First Affiliated Hospital, China Medical University, Shenyang, China.
authors.forename: Yexiang
authors.initials: Y
authors.lastname: Huang
authors.affiliation: Urology Institute, University Hospitals Case Medical Center, and Department of Urology, Case Western Reserve University School of Medicine, Cleveland, OH.
authors.forename: Firouz
authors.initials: F
authors.lastname: Daneshgari
authors.affiliation: Urology Institute, University Hospitals Case Medical Center, and Department of Urology, Case Western Reserve University School of Medicine, Cleveland, OH. Electronic address: guiming.liu@case.edu.
authors.forename: Guiming
authors.initials: G
authors.lastname: Liu
mesh_terms: D000818:Animals; D002404:Catheterization; D004195:Disease Models, Animal; D030762:Estrous Cycle; D005260:Female; D051379:Mice; D008810:Mice, Inbred C57BL; D011312:Pressure; D014521:Urethra / Q000473:pathology; D014550:Urinary Incontinence, Stress / Q000628:therapy*; D014554:Urination; D014621:Vagina / Q000473:pathology*