219 INHIBITORY EFFECT OF INTRATHECAL GALANIN ON THE MICTURITION REFLEX IN URETHANE-ANESTHETIZED RATS (2011)

You have accessJournal of UrologyBladder and Urethra: Anatomy, Physiology and Pharmacology1 Apr 2011219 INHIBITORY EFFECT OF INTRATHECAL GALANIN ON THE MICTURITION REFLEX IN URETHANE-ANESTHETIZED RATS Masashi Honda, Mayuko Matsumoto, Seiya Inoue, Nobuyuki Hinata, Atsushi Takenaka, Michael Chancellor, and Naoki Yoshimura Masashi HondaMasashi Honda Yonago, Japan , Mayuko MatsumotoMayuko Matsumoto Yonago, Japan , Seiya InoueSeiya Inoue Yonago, Japan , Nobuyuki HinataNobuyuki Hinata Yonago, Japan , Atsushi TakenakaAtsushi Takenaka Yonago, Japan , Michael ChancellorMichael Chancellor Royal Oak, MI , and Naoki YoshimuraNaoki Yoshimura Pittsburgh, PA View All Author Informationhttps://doi.org/10.1016/j.juro.2011.02.329AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Galanin, a 29 amino acid peptide, distributes widely in the peripheral and central nervous systems, including the primary afferents, dorsal horn interneurons and the descending bulbospinal tracts. Recent studies have demonstrated that galanin is involved in nociceptive responses, especially in the transmission of nociceptive information in the spinal cord. However, it is not known whether galanin has a role in the control of the micturition reflex. Therefore, we investigated the effects of galanin on the micturition reflex in rats. METHODS Continuous cystometrograms (CMG, 0.04ml/min infusion rate) were performed in female Sprague-Dawley rats (225–248 g) under urethane anesthesia. After stable micturition cycles were established, galanin was administered intrathecally to evaluate changes in bladder activity. In experiments examining the role of opioid systems, galanin was administered intrathecally when the first bladder contraction was observed after intrathecal administration of naloxone, an opioid receptor antagonist. Micturition parameters were recorded and compared before and after drug administration. RESULTS Intrathecal administration of galanin at 1, 3 and 10 μg (n=6 per dose) increased intercontraction intervals in a dose-dependent fashion to 117.7 ± 2.4%, 141.1 ± 7.8% and 159.8 ± 12.5% of the control value, respectively (p<0.01). These inhibitory effects were seen immediately after administration and returned to the pre-control level within 70 minutes. Intrathecal administration of galanin at 1, 3 and 10 μg (n=6 per dose) also increased pressure thresholds in a dose-dependent fashion to 9.52 ± 0.98 cmH2O, 11.2 ± 1.12 cmH2O and 12.9 ± 1.67 cmH2O, respectively (p<0.01). There were no significant changes in baseline pressure or residual urine at any doses tested. These inhibitory effects of galanin (10 μg, n=6) were antagonized by intrathecal administration of naloxone (10 μg, n=6). CONCLUSIONS These results indicate that in urethane-anesthetized rats galanin inhibits the micturition reflex through the opioid mechanism. Thus, galanin could be effective for the treatment of bladder dysfunction such as overactive bladder. © 2011 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 185Issue 4SApril 2011Page: e90 Advertisement Copyright & Permissions© 2011 by American Urological Association Education and Research, Inc.MetricsAuthor Information Masashi Honda Yonago, Japan More articles by this author Mayuko Matsumoto Yonago, Japan More articles by this author Seiya Inoue Yonago, Japan More articles by this author Nobuyuki Hinata Yonago, Japan More articles by this author Atsushi Takenaka Yonago, Japan More articles by this author Michael Chancellor Royal Oak, MI More articles by this author Naoki Yoshimura Pittsburgh, PA More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...