PD55-04 TIBIAL AND PUDENDAL NEUROMODULATION OF SPINAL NEURON ACTIVITY INDUCED BY BLADDER DISTENTION

Abstract

You have accessJournal of UrologyBladder & Urethra: Anatomy, Physiology & Pharmacology II1 Apr 2018PD55-04 TIBIAL AND PUDENDAL NEUROMODULATION OF SPINAL NEURON ACTIVITY INDUCED BY BLADDER DISTENTION Todd Yecies, Shun Li, Yan Zhang, Daniel Cai, Bing Shen, Jicheng Wang, James Roppolo, William De Groat, and Changfeng Tai Todd YeciesTodd Yecies More articles by this author , Shun LiShun Li More articles by this author , Yan ZhangYan Zhang More articles by this author , Daniel CaiDaniel Cai More articles by this author , Bing ShenBing Shen More articles by this author , Jicheng WangJicheng Wang More articles by this author , James RoppoloJames Roppolo More articles by this author , William De GroatWilliam De Groat More articles by this author , and Changfeng TaiChangfeng Tai More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2018.02.2624AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Neuromodulation is an FDA-approved treatment for overactive bladder (OAB), however the mechanisms underlying neuromodulation are not completely understood. Prior studies have suggested that perigenital stimulation (PGS), pudendal nerve stimulation (PNS) and tibial nerve stimulation (TNS) can alter afferent sensory signaling from the bladder, however the sites of action (spinal or supraspinal) for bladder neuromodulation are not clear. We present a novel approach to identify individual bladder related neurons (BRNs) and assess the effect of PGS, PNS, and TNS on BRN activity. METHODS The S2 level of the spinal cord was exposed in α-chloralose anesthetized cats. Bladder pressure was modulated using a urethral catheter attached to an adjustable height reservoir. Using a tungsten micro-electrode lowered into the S2 spinal cord, individual neurons with firing patterns that changed with bladder pressure were identified. The effect of PGS, PNS (5Hz, 0.2 ms) at 2 times the threshold to induce anal twitch (2T), and TNS (5Hz, 0.2 ms) at 2 and 4 times the threshold to induce toe movement (2 and 4T) on BRN activity were studied. Naloxone, an opioid receptor antagonist, was administered intravenously (1.0mg/kg) to a subset of cats to determine the role of opiate signaling in PNS and TNS inhibition of BRN signaling. RESULTS A total of 19 BRNs were identified in 12 cats. Of these, 18 were positively stimulated by increased bladder pressure, while 1 was inhibited by rises in bladder pressure. BRNs demonstrated increased activity with increased bladder pressure (p<0.01). Both PNS and TNS at 2T significantly inhibited BRN activity at bladder pressures of 10, 20, 30, and 40 cm H2O (p<0.05). Perigenital stimulation inhibited BRN activity at all tested bladder pressures (p=0.037). TNS at 4T for a 30 minute period provided a brief post-stimulation inhibitory effect at 20-40cm H2O (p<0.01) which dissipated within a 5 minute recovery window. Administration of IV naloxone increased background neuron activity (p=0.04) but had no effect on PNS and TNS-mediated inhibition of BRN activity. CONCLUSIONS Individual BRNs could be reliably identified within the feline S2 spinal cord. Perigenital stimulation, TNS and PNS significantly inhibited BRN activity at different bladder pressures. TNS and PNS inhibition was not effected by naloxone, suggesting non-opiate mediated inhibition. Through this novel technique of measuring BRN activity, the effect of pharmacologic or neuromodulatory interventions to manage OAB can be more precisely delineated to reveal the potential sites of action. © 2018FiguresReferencesRelatedDetails Volume 199Issue 4SApril 2018Page: e1057 Advertisement Copyright & Permissions© 2018MetricsAuthor Information Todd Yecies More articles by this author Shun Li More articles by this author Yan Zhang More articles by this author Daniel Cai More articles by this author Bing Shen More articles by this author Jicheng Wang More articles by this author James Roppolo More articles by this author William De Groat More articles by this author Changfeng Tai More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...