You have accessJournal of UrologyStone Disease: Basic Research I1 Apr 20122076 SPINAL ALPHA1-ADRENOCEPTORS MODIFY IN VIVO PERISTALSIS OF THE OBSTRUCTED RAT URETER Luca Villa, Claudius Fullhase, Christian Stief, Patrizio Rigatti, Francesco Montorsi, and Petter Hedlund Luca VillaLuca Villa Milan, Italy More articles by this author , Claudius FullhaseClaudius Fullhase Munich, Germany More articles by this author , Christian StiefChristian Stief Munich, Germany More articles by this author , Patrizio RigattiPatrizio Rigatti Milan, Italy More articles by this author , Francesco MontorsiFrancesco Montorsi Milan, Italy More articles by this author , and Petter HedlundPetter Hedlund Linköping, Sweden More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2012.02.2242AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES alpha1-adrenoceptor (−AR) antagonists may facilitate ureter stone passage in humans. The site of action of these drugs is presumed to be in the ureter. No information is available on spinal alpha1-ARs and ureter function. This study evaluated effects of intrathecal tamsulosin on intraureteral pressure and peristalsis in an in vivo rat model for partial ureter obstruction. METHODS After ethical approval, 11 male Sprague Dawley rats were used. Under anesthesia, a polyethylene(PE)-10 catheter was implanted into the subarachnoidal space (thoracic level) for i.t. delivery of tamsulosin (10 ìg).Saline was bilaterally infused at 0.4ml/hour (=normal urine production) via PE-10 catheters proximal in the ureters. The psoas muscle was sutured around the distal left ureter to create a partial obstruction. The right ureter was intact. Mean arterial blood pressure (MAP; carotid artery), and left and right ureter pressures were recorded via a Biopac system.Values are mean±standard error of the mean. T-test was used for comparisons. RESULTS At baseline, similar spontaneous peristaltic pressure waves were recorded in both ureters. Obstruction increased minimum and maximum pressures to 67.1±5.4 and 77.1±7.0 cmH2O. The normal ureter had minimum and maximum pressures of 21.4±2.5 and 29.8±2.2 cmH2O. Intrathecal tamsulosin had no effects on the normal ureter pressure, but reduced the minimum pressure in the obstructed ureter by 25.0±5.7% (p<0.01) and the maximum pressure by 29.9±5.7% (p<0.001). Tamsulosin (i.t.) reduced the area under the curve of the obstructed ureter by 25.0±4.1% (p<0.01). The frequencies of spontaneous peristaltic pressure waves were reduced from 5.8±0.8 to 4.1±1.0 (normal; p<0.05) and from 3.9±0.7 to 2.7±0.6 per minute (obstructed; p<0.01). The pressure wave amplitude before and after tamsulosin (i.t.) was 9.7±2.4 and 12.9±3.3 cmH2O (obstructed ureter; p<0.05), and 8.4±0.6 and 9.0±2.4 (normal ureter). The MAP was reduced from 152±9 cmH2O to 120±10 cmH2O (p<0.05).Vehicle had no effect on ureter peristalsis. CONCLUSIONS Intrathecal tamsulosin reduces the intraureteral pressure of obstructed ureters but not of normal ureters. Spinal alpha1-ARs appear to be involved in regulation of ureter function. These signals may be upregulated in obstructed ureters. Besides a peripheral site of action in stone expulsion therapy, alpha1-AR antagonists may also have effects on the ureter via spinal signals. © 2012 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 187Issue 4SApril 2012Page: e837 Advertisement Copyright & Permissions© 2012 by American Urological Association Education and Research, Inc.MetricsAuthor Information Luca Villa Milan, Italy More articles by this author Claudius Fullhase Munich, Germany More articles by this author Christian Stief Munich, Germany More articles by this author Patrizio Rigatti Milan, Italy More articles by this author Francesco Montorsi Milan, Italy More articles by this author Petter Hedlund Linköping, Sweden More articles by this author Expand All Advertisement Advertisement PDF DownloadLoading ...