title: Free radical damage as a biomarker of bladder dysfunction after partial outlet obstruction and reversal.
abstract: OBJECTIVE
  To investigate the use of free-radical generation as a result of protein carbonylation and nitrotyrosination to characterize the level of bladder dysfunction after partial bladder outlet obstruction (PBOO) and reversal.
  
  
  METHODS
  We surgically created PBOO in male New Zealand White rabbits; after 4 weeks of PBOO, one group of six rabbits was assessed, while the PBOO was relieved in two additional groups of six rabbits each that were assessed at 4 and 8 weeks after relieving the PBOO. Six sham-operated rabbits served as controls. Sedated rabbits were assessed by cystometry and the bladders were then removed for contractile, histological and molecular studies. Western blotting was used to determine the level of carbonylation and nitrotyrosination at the protein level.
  
  
  RESULTS
  The PBOO group had significant decreases in the contractile responses to field stimulation, ATP, carbachol and KCl. The responses to all forms of stimulation increased significantly at 4 weeks after reversal, and further increased to near normal levels by 8 weeks. Similarly, compliance and cystometric values also returned to near normal values after reversal. The hypertrophied smooth muscle of the obstructed bladders regressed to near-normal size. There was a significant increase in the level of carbonylation and nitrotyrosination after PBOO, and a progressive decrease in the 4-week reversal groups, nearing control values by 8 weeks.
  
  
  CONCLUSIONS
  Significantly increased carbonylation and nitrotyrosination levels after PBOO correlated with the severe dysfunction in the obstructed rabbits. Similarly, decreased levels of oxidation and nitration correlated with the functional recovery after reversal.
authors.affiliation: Division of Urology, Department of Surgery, Chang Gung Memorial Hospital, Chia-Yi, Taiwan.
authors.forename: Wei-Yu
authors.initials: WY
authors.lastname: Lin
authors.forename: Ahmet
authors.initials: A
authors.lastname: Guven
authors.forename: Yung-Shun
authors.initials: YS
authors.lastname: Juan
authors.forename: Paul
authors.initials: P
authors.lastname: Neuman
authors.forename: Catherine
authors.initials: C
authors.lastname: Whitbeck
authors.forename: Paul
authors.initials: P
authors.lastname: Chichester
authors.forename: Barry
authors.initials: B
authors.lastname: Kogan
authors.forename: Robert M
authors.initials: RM
authors.lastname: Levin
authors.forename: Anita
authors.initials: A
authors.lastname: Mannikarottu
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000378:metabolism*; D008297:Male; D009119:Muscle Contraction / Q000502:physiology; D050050:Protein Carbonylation / Q000502:physiology; D011817:Rabbits; D026361:Reactive Nitrogen Species / Q000378:metabolism*; D017382:Reactive Oxygen Species / Q000378:metabolism*; D001743:Urinary Bladder / Q000503:physiopathology*; D001748:Urinary Bladder Neck Obstruction / Q000503:physiopathology*
chemical_list: D015415:Biomarkers; D026361:Reactive Nitrogen Species; D017382:Reactive Oxygen Species