title: Second prize: In-vivo physiological impact of alpha blockade on the porcine ureter with distal ureteral obstruction.
abstract: OBJECTIVE
  Alpha blockade has been well described clinically for expulsion of distal ureteral stone. However, the in-vivo effects of α-blockade on ureteral dynamics during stone passage are not clear. We studied the effects of oral alfuzosin on ureteral pressure and peristalsis in a distally obstructed porcine ureter.
  
  
  METHODS
  Twenty-four female domestic swine (75-82 kg) were incorporated into the study. The study was powered to detect a 30% difference in distal ureteral pressure, with a secondary endpoint of frequency of ureteral peristalsis. The animals were divided into four equal groups: a control group without α-blockade or ureteral obstruction, a group with α-blockade and no ureteral obstruction, a cohort without α-blockade but with distal ureteral obstruction, and a group with α-blockade and distal obstruction. Peristalsis was measured by a magnetic sensor and ureteral pressure through a 5F ureteral balloon catheter. Observations were recorded for 10-minute intervals every hour for 5 consecutive hours.
  
  
  RESULTS
  There was increase in ureteral pressure and peristaltic rate with distal ureteral obstruction (p < 0.01). Alpha blockade did not produce significant changes in the above parameters with or without ureteral obstruction compared with the nonmedicated groups. We observed a 0.2 mm Hg lower increase in change of ureteral pressure during peristalsis compared with resting ureteral pressure (delta pressure) in the treated obstructed model (95% confidence interval: -0.55 -0.10; p = 0.06).
  
  
  CONCLUSIONS
  In the porcine model, alfuzosin appears to decrease the delta pressure in the distal ureter during obstruction; however, statistical significance was not reached. Further investigation into the in-vivo physiology of medical expulsive therapy is warranted.
authors.affiliation: Division of Urology, University of Kentucky, Lexington, Kentucky 40536, USA. jay.page@uky.edu
authors.forename: Jay Blain
authors.initials: JB
authors.lastname: Page
authors.forename: Suzanne
authors.initials: S
authors.lastname: Humphreys
authors.forename: Daniel
authors.initials: D
authors.lastname: Davenport
authors.forename: Paul
authors.initials: P
authors.lastname: Crispen
authors.forename: Ramakrishna
authors.initials: R
authors.lastname: Venkatesh
mesh_terms: D058668:Adrenergic alpha-1 Receptor Antagonists / Q000494:pharmacology* / Q000627:therapeutic use*; D000818:Animals; D001363:Awards and Prizes; D004576:Electromyography; D005260:Female; D010528:Peristalsis / Q000187:drug effects; D011312:Pressure; D034421:Sus scrofa; D014513:Ureter / Q000187:drug effects* / Q000503:physiopathology; D014517:Ureteral Obstruction / Q000188:drug therapy* / Q000503:physiopathology
chemical_list: D058668:Adrenergic alpha-1 Receptor Antagonists