title: Adherence junctions and cadherin-11 in normal and overactive human detrusor smooth muscle cells.
abstract: OBJECTIVE
  We investigated whether analysis of adherence junctions in human detrusor could be used as a diagnostic tool to determine detrusor overactivity.
  
  
  METHODS
  We characterized the protein composition of adherence junctions in the human bladder using cadherin-11 since our group previously found that cadherin-11 could be an integral structural protein of adherence junctions. We obtained a total of 46 biopsies from 23 patients categorized into 4 groups, including 5 who were normal, and 6 each with neurogenic disease with detrusor overactivity, bladder outlet obstruction with detrusor overactivity and idiopathic detrusor overactivity. Specimens were processed to study cadherin-11 expression using combined immunohistochemical and immunogold electron microscopy techniques. Cadherin-11 expression was semiquantitatively analyzed and correlated to muscle fascicle structure and collagen in the extracellular spaces.
  
  
  RESULTS
  Immunogold labeling showed highly specific cadherin-11 expression at adherence junctions in detrusor smooth muscle cells. During immunohistochemical staining a wide variety of cadherin-11 expression and fascicle structure was found in the same specimen. No correlation was noted between detrusor overactivity and cadherin-11 expression. However, cadherin-11 seemed to be down-regulated with intercellular space widening and collagenosis.
  
  
  CONCLUSIONS
  Cadherin-11 is an integral structural protein of the adherence junction. Defects in the overactive detrusor are highly punctate. Quantitative analysis of adherence junctions using biopsy cannot replace urodynamic evaluation as a predictor of detrusor overactivity in the human bladder.
authors.affiliation: Department of Urology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands. k.kuijpers@umcn.uro.nl
authors.forename: Kamiel A J
authors.initials: KA
authors.lastname: Kuijpers
authors.forename: John P F A
authors.initials: JP
authors.lastname: Heesakkers
authors.forename: Theo G M
authors.initials: TG
authors.lastname: Hafmans
authors.forename: Jack A
authors.initials: JA
authors.lastname: Schalken
mesh_terms: D022005:Adherens Junctions / Q000378:metabolism*; D000368:Aged; D001706:Biopsy; D015820:Cadherins / Q000378:metabolism*; D015536:Down-Regulation; D005260:Female; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D008297:Male; D008854:Microscopy, Electron; D008875:Middle Aged; D001748:Urinary Bladder Neck Obstruction / Q000378:metabolism*; D053201:Urinary Bladder, Overactive / Q000175:diagnosis* / Q000378:metabolism*
chemical_list: D015820:Cadherins; C086960:osteoblast cadherin