title: Disruption of bladder epithelium barrier function after spinal cord injury.
abstract: Neural-epithelial interactions are hypothesized to play an important role in bladder function. We determined whether spinal cord injury (SCI) altered several indicators of urinary bladder epithelium barrier function, including continuity of the surface umbrella cell layer, transepithelial resistance (TER), and urea and water permeability. Within 2 h of SCI, significant changes in uroepithelium were noted, including disruption of the surface umbrella cells and an approximately 50% decrease in TER. By 24 h, TER reached a minimum and was accompanied by significant increases in water and urea permeability. Regeneration of the surface uroepithelium was accomplished by 14 days after SCI and was accompanied by a return to normal TER and urea and water permeabilities. This early disruption of the uroepithelial permeability and accompanying changes in uroepithelial morphology were prevented by pretreatment with hexamethonium (a blocker of ganglion transmission), indicating involvement of sympathetic or parasympathetic input to the urinary bladder. In addition, prior treatment with capsaicin worsened the effect of SCI on uroepithelial permeability, suggesting that capsaicin-sensitive afferents may play a protective role in the process. These results demonstrate that SCI results in a significant disruption of the urinary bladder uroepithelium and that these changes may be mediated in part by an interaction with bladder nerves.
authors.affiliation: Laboratory of Epithelial Cell Biology, Department of Cell Biology and Physiology, University of Pittsburgh, Pittsburgh, Pennsylvania 15261, USA. gla6@pitt.edu
authors.forename: Gerard
authors.initials: G
authors.lastname: Apodaca
authors.forename: Susanna
authors.initials: S
authors.lastname: Kiss
authors.forename: Wily
authors.initials: W
authors.lastname: Ruiz
authors.forename: Susan
authors.initials: S
authors.lastname: Meyers
authors.forename: Mark
authors.initials: M
authors.lastname: Zeidel
authors.forename: Lori
authors.initials: L
authors.lastname: Birder
mesh_terms: D000818:Animals; D002211:Capsaicin / Q000494:pharmacology; D017097:Electric Impedance; D004848:Epithelium / Q000503:physiopathology / Q000648:ultrastructure; D005260:Female; D005730:Ganglionic Blockers / Q000494:pharmacology; D018738:Hexamethonium / Q000494:pharmacology; D008854:Microscopy, Electron; D008855:Microscopy, Electron, Scanning; D010539:Permeability; D051381:Rats; D017207:Rats, Sprague-Dawley; D012016:Reference Values; D013119:Spinal Cord Injuries / Q000473:pathology / Q000503:physiopathology*; D013997:Time Factors; D014508:Urea / Q000378:metabolism; D001743:Urinary Bladder / Q000503:physiopathology* / Q000648:ultrastructure; D014867:Water / Q000378:metabolism
chemical_list: D005730:Ganglionic Blockers; D014867:Water; D018738:Hexamethonium; D014508:Urea; D002211:Capsaicin