title: Neuromodulation reduces urinary frequency in rats with hydrochloric acid-induced cystitis.
abstract: OBJECTIVE
  To evaluate the effect of sacral neuromodulation on interstitial cystitis (IC) and determine the underlying mechanism of neuromodulation in the treatment of IC. Materials and methods Twenty Sprague-Dawley rats (body weight 220-250 g) were randomly divided into four equal groups; normal controls, a sham treatment (IC induced by 0.4 mol/L HCl, + saline), a second sham treatment (HCl-induced IC + acetic acid) and a stimulated group (HCl-induced IC + acetic acid, with electrical stimulation). In the last group bilateral electrodes were implanted into the S1 dorsal foramina and electrical stimulation applied for 8 h/day for 3 weeks. Acetic acid was instilled into the bladder to induce c-fos expression. After 3 weeks the rats were perfused with 4% paraformaldehyde, spinal segments dissected out and an immunocytochemical method used to stain the segments for fos protein encoded byc-fos.
  
  
  RESULTS
  The mean (SEM) micturition frequency (voids/17 h) in the sham groups increased from 10.8 (2.7) to 23.4 (3.4) 3 weeks after the intravesical instillation of HCl. The micturition frequency in the stimulated group, at 16.2 (2.7), was significantly less than in the sham group (P = 0.04) after electrical stimulation for 3 weeks. There was no significant difference in the mean (SEM) number of fos-positive neurones in the L6 spinal cord segment between the stimulated and the sham + acetic acid group, at 43.6 (9.4) and 35.8 (7.8) cells/section, respectively (P = 0.32).
  
  
  CONCLUSIONS
  In rats with HCl-induced cystitis, electrical stimulation reduced the micturition frequency, but not by inhibiting afferent c-fibre activity.
authors.affiliation: Urology Research Laboratory, Division of Urology, Toronto Western Hospital, University of Toronto, Toronto, Canada.
authors.forename: Y
authors.initials: Y
authors.lastname: Wang
authors.forename: Y
authors.initials: Y
authors.lastname: Zhou
authors.forename: M S
authors.initials: MS
authors.lastname: Mourad
authors.forename: M M
authors.initials: MM
authors.lastname: Hassouna
mesh_terms: D000818:Animals; D018856:Cystitis, Interstitial / Q000139:chemically induced / Q000628:therapy*; D004599:Electric Stimulation Therapy / Q000379:methods*; D004566:Electrodes; D051381:Rats; D017207:Rats, Sprague-Dawley; D012447:Sacrum / Q000294:innervation; D016055:Urinary Retention / Q000628:therapy*