288 INVOLVEMENT OF CANNABINOID RECEPTOR TYPE 2 IN MICTURITION IN MICE

Abstract

You have accessJournal of UrologyBladder and Urethra: Anatomy, Physiology and Pharmacology (I)1 Apr 2013288 INVOLVEMENT OF CANNABINOID RECEPTOR TYPE 2 IN MICTURITION IN MICE Lysanne Campeau, Claudius Füllhase, Norifumi Sawada, Christian Gratzke, Petter Hedlund, Allyn Howlett, and Karl-Erik Andersson Lysanne CampeauLysanne Campeau Winston-Salem, NC More articles by this author , Claudius FüllhaseClaudius Füllhase Munich, Germany More articles by this author , Norifumi SawadaNorifumi Sawada Winston-Salem, NC More articles by this author , Christian GratzkeChristian Gratzke Munich, Germany More articles by this author , Petter HedlundPetter Hedlund Milan, Italy More articles by this author , Allyn HowlettAllyn Howlett Winston-Salem, NC More articles by this author , and Karl-Erik AnderssonKarl-Erik Andersson Winston-Salem, NC More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2013.02.1672AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Systemic administration of cannabinoid (CB) receptor agonists affects bladder function, but the contribution of individual CB receptors during normal micturition has not been clearly defined. Our goal was to study if differences in urodynamic endpoints or in vitro bladder contractility exist between CB receptor type 2 knockout (CB2 −/−) and C57BL/6J control mice following CB2 receptor modulators. METHODS After ethical approval, female C57BL/6J (n=15) and CB2 −/− mice (n=15) underwent bladder catheterization three days prior to cystometry. Cystometry was performed in awake animals at baseline, and after sequentially giving of HU308 (CB2 agonist) followed by AM630 (CB2 antagonist). Comparisons of effects were made with ANOVA of repeated measures. Bladders were extracted for in vitro assessment of contractility to carbachol and electrical field stimulation (EFS). RESULTS Bladder capacity (BC) in C57BL/6J mice was increased from 0.0322 ± 0.0047 (baseline) to 0.0397 ± 0.0053 mL by HU308, and then decreased to 0.0324 ± 0.0058 mL after AM630 (p<0.05). Similarly, intercontraction interval (ICI) increased from 77.2 ± 11.4 sec to 95.2 ± 12.7 sec with HU308, and then decreased to 77.8 ± 14.0 sec with AM630. CB2 −/− mice had at baseline a lower maximal pressure (MP) (26.7 ± 1.4 vs 32.7 ± 1.4 cm H2O), basal pressure (BP) (12.0 ± 1.7 vs 17.3 ± 1.8 cm H2O), and area under the curve (AUC) (16.9 ± 1.6 vs 22.7 ± 1.9), and a higher ICI (139.9 ± 19.6 vs 77.2 ± 11.4 sec), BC (0.0583 ± 0.00819 vs 0.0322 ± 0.0048 mL) and compliance (0.0058 ± 0.0008 vs 0.0037 ± 0.0004 mL/cm H2O) than controls (p<0.05). AM630 in CB2 −/− mice increased ICI (142.3 ± 19.5 vs 173.4 vs 22.3 sec), BC (0.0722 ± 0.0093 vs 0.0593 ± 0.0081 mL), MP (28.3 ± 1.5 vs 24.4 ± 1.3 cm H2O) and TP (23.9 ± 1.8 vs 20.1 ± 1.3 cm H2O), and decreased BP (10.0 ± 1.6 vs 12.0 ± 1.7 cm H2O) (p<0.05). There were no differences in contractility after carbachol or EFS between both groups. CONCLUSIONS Indicating a role for the CB2 receptor in afferent micturition signals in normal mice, CB2 receptor agonism modified ICI and BC. CB2 −/− mice had lower pressures, along with a longer ICI and larger BC and compliance than C57BL/6J. These differences may be explained by compensatory up-regulation of other signals due to the knockout of CB2. Further investigations are necessary to understand the reverse effects by AM630 in CB2−/− and control mice. © 2013 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 189Issue 4SApril 2013Page: e117 Advertisement Copyright & Permissions© 2013 by American Urological Association Education and Research, Inc.MetricsAuthor Information Lysanne Campeau Winston-Salem, NC More articles by this author Claudius Füllhase Munich, Germany More articles by this author Norifumi Sawada Winston-Salem, NC More articles by this author Christian Gratzke Munich, Germany More articles by this author Petter Hedlund Milan, Italy More articles by this author Allyn Howlett Winston-Salem, NC More articles by this author Karl-Erik Andersson Winston-Salem, NC More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...