You have accessJournal of UrologyBladder and Urethra: Anatomy, Physiology and Pharmacology (II)1 Apr 2013544 ROLE OF CANNABINOID AND TRPV1 RECEPTORS IN THE SPINAL MECHANISMS OF MICTURITION IN THE NORMAL RAT Lysanne Campeau, Claudius Füllhase, 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 , 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.2013.02.1939AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Systemic administration of cannabinoid (CB) receptor agonists and fatty acid amide hydrolase (FAAH) inhibitors affects bladder function, but whether the main site of action is peripheral tissues or the central nervous system is unknown. Intrathecal (IT) CBs have been shown to produce antinociception in neuropathic pain animal models. Many of these compounds also act at the TRPV1 receptor. Our goal was to determine the effects of IT CB receptor agonists and the impact of TRPV1 activation on bladder function of normal rats when spinal degradation of endogenous CBs is inhibited. METHODS In female rats, bladder and IT catheters were inserted prior to cystometric evaluation. Urodynamic parameters were recorded in conscious animals at baseline, and after each drug. The first part of the study involved two groups of animals with incremental doses, preceded by vehicle, of methanandamide (MA) (5, 10, 20, 40 μg), a selective CB1 agonist and WIN 55212-2 (10, 20, 40 μg), a non-selective CB agonist. The second part involved two other groups of animals: the first received IT SB366791 (200 nmol), a selective TRPV1 antagonist, followed by intraperitoneal oleoyl ethyl amide (OeTA) (0.75 mg/kg), a FAAH inhibitor, and finally IT MA (100 μg); the second group received IT vehicle (DMSO) for SB366791, followed by OeTA, and IT MA. Parameters were measured in absolute values and calculated as change from baseline. RESULTS The micturition pressures did not change after vehicle or drug administration across all groups. In the MA only group, bladder capacity (BC) significantly increased from baseline after 40 μg administration (0.62 vs 0.91 mL, p<0.05). BC also significantly increased after administration of 40 μg of WIN 55212-2 when compared to baseline (0.80 vs 1.04 mL, p<0.01) and to vehicle (0.82 vs 1.04 mL, p<0.05). Micturition volume (MV) increased from baseline after 20 μg administration of WIN 55212-2 (0.76 vs 1.05 mL, p<0.05). In the animals that received vehicle prior to OeTA and MA, we observed a significant increase from baseline in the BC (13.9%) and MV (31.8%) following both systemic OeTA and IT MA (p<0.05). While in the animals that were given SB366791, there were no significant changes from baseline in BC or MV following systemic OeTA and IT MA. CONCLUSIONS IT CB receptor agonist administration increases BC in normal rats. Both drugs may activate TRPV1 along with CB receptors. IT TRPV1 antagonist administration abolished the effects of both MA and OeTA on BC and MV. This suggests that spinal TRPV1 activation is involved in effects by FAAH substrates and MA on afferent signaling in micturition. © 2013 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 189Issue 4SApril 2013Page: e223 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 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 ...