title: Effects of pentoxifylline on renal structure after urethral obstruction in rat: A stereological study.
abstract: OBJECTIVE
  Chronic renal failure due to tubulointerstitial fibrosis is one of complications of lower urinary tract obstruction. Since pentoxifylline is a xanthine derivative that inhibits some inflammatory mediators, we conducted this study to investigate whether pentoxifylline inhibits renal fibrosis in a rat model of partial urethral obstruction (PUO).
  
  
  METHODS
  All the rats underwent experimental PUO. Then, the animals were divided randomly into two groups: positive control group and experimental group. The experimental group received pentoxifylline 100 mg/kg per day via oral gavages for 4-weeks. The control group received the same dose of normal saline. After 4-weeks, all the rats underwent left nephrectomy. Kidney volume and weight and fractional and absolute volumes of the glomeruli, tubules, interstitium and vessels were determined with stereological methods. To reduce the workload of reference (kidney) volume estimation, the total kidney volume was determined after estimation of tissue shrinkage on isotropic uniform random histological sections. The total volume (amount) of each renal structure including fibrosis was estimated to avoid the bias conclusion due to relying on volume density alone.
  
  
  RESULTS
  The absolute volume of interstitial fibrosis was lower in the experimental group (PUO with pentoxifylline treatment) (~84%; p ≤0.006) in comparison with the control group (PUO with no treatment).
  
  
  CONCLUSIONS
  Pentoxifylline reduces interstitial renal fibrosis after partial urethral obstruction in rats.
authors.affiliation: Histomorphometry & Stereology Research Centre, Shiraz University of Medical Sciences, Shiraz, Iran.
authors.forename: Mehdi
authors.initials: M
authors.lastname: Shirazi
authors.affiliation: Histomorphometry & Stereology Research Centre, Shiraz University of Medical Sciences, Shiraz, Iran.
authors.forename: Ali
authors.initials: A
authors.lastname: Noorafshan
authors.affiliation: Department of Urology, Shahid Faghihi Hospital, Shiraz University of Medical Sciences, Shiraz, Iran.
authors.forename: Amir
authors.initials: A
authors.lastname: Farrokhi
keywords: partial urethral obstruction; pentoxifylline; stereology