PD24-03 ACTIVATION OF GROUP I AND III METABOTROPIC GLUTAMATE RECEPTORS INFLUENCES THE MICTURITION REFLEX IN URETHANE-ANESTHETIZED RATS

Abstract

You have accessJournal of UrologyBladder & Urethra: Anatomy, Physiology & Pharmacology II (PD24)1 Apr 2020PD24-03 ACTIVATION OF GROUP I AND III METABOTROPIC GLUTAMATE RECEPTORS INFLUENCES THE MICTURITION REFLEX IN URETHANE-ANESTHETIZED RATS Masashi Honda*, Ryutaro Shimizu, Shogo Teraoka, Ryoma Nishikawa, Yusuke Kimura, Panagiota Tsounapi, Hideto Iwamoto, Shuichi Morizane, Katsuya Hikita, and Atsushi Takenaka Masashi Honda*Masashi Honda* More articles by this author , Ryutaro ShimizuRyutaro Shimizu More articles by this author , Shogo TeraokaShogo Teraoka More articles by this author , Ryoma NishikawaRyoma Nishikawa More articles by this author , Yusuke KimuraYusuke Kimura More articles by this author , Panagiota TsounapiPanagiota Tsounapi More articles by this author , Hideto IwamotoHideto Iwamoto More articles by this author , Shuichi MorizaneShuichi Morizane More articles by this author , Katsuya HikitaKatsuya Hikita More articles by this author , and Atsushi TakenakaAtsushi Takenaka More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000000881.03AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: The modulatory effects of glutamate are mediated by activation of metabotropic glutamate receptors (mGluRs). Eight mGluRs (mGluR1−8) have been classified into three groups (I−III) according to their sequence homology. Group I (mGluRI; mGluR1 and mGluR5), group II (mGluRII; mGluR2 and mGluR3), and group III (mGluRIII; mGluR4, mGluR6, mGluR7, and mGluR8) mGluRs are widely distributed throughout the central nervous system. However, the role of mGluRs in the regulation of neural mechanisms controlling the micturition reflex remains unknown. Therefore, we assessed whether RS-3,5-dihydroxyphenylglycine (RS-3,5-DHPG), a selective mGluRI agonist, 2R,4R-4-aminopyrrolidine-2,4-dicarboxylate (2R,4R-APDC), a selective mGluRII agonist, and L-(+)-2-amino-4-phosphonobutyric acid (L-AP4), a selective mGluRIII agonist, affect the micturition reflex in urethane-anesthetized rats. METHODS: Adult female Sprague-Dawley rats weighing 242 to 268 g were used. Continuous cystometrograms were performed for two groups of urethane-anesthetized rats. The first group of 54 rats was used for intracerebroventricular administration of 1−10 µg of RS-3,5-DHPG, 2R,4R-APDC, or L-AP4 via a catheter inserted into the lateral ventricle. In the second group of 54 rats, 1−10 μg of RS-3,5-DHPG, 2R,4R-APDC, or L-AP4 was administered via an intrathecal catheter. Cystometric parameters were recorded and compared before and after drug administration. RESULTS: Intracerebroventricular administration of RS-3,5-DHPG at doses of 1, 3, and 10 µg (n = 6 per dose) increased the intercontraction interval in a dose-dependent manner to 111.8 ± 9.4%, 121.8 ± 8.7%, and 129.2 ± 10.7% of the control value, respectively (p < 0.01). Intracerebroventricular administration of L-AP4 at doses of 1, 3, and 10 µg (n = 6 per dose) showed similar effects, with the intercontraction interval increasing to 115.3 ± 11.5%, 128.6 ± 9.5%, and 132.2 ± 13.6% of the control value, respectively (p < 0.01). Intrathecal administration of RS-3,5-DHPG and L-AP4 at doses of 1, 3, and 10 µg (n = 6 per dose) also increased the intercontraction interval in a dose-dependent manner. However, intracerebroventricular or intrathecal administration of 2R,4R-APDC did not affect the intercontraction interval, maximum voiding pressure, or baseline pressure at any tested dose. CONCLUSIONS: These results indicate that activation of mGluRI and mGluRIII could inhibit the spinal and supraspinal micturition reflexes in urethane-anesthetized rats. Source of Funding: None © 2020 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 203Issue Supplement 4April 2020Page: e533-e533 Advertisement Copyright & Permissions© 2020 by American Urological Association Education and Research, Inc.MetricsAuthor Information Masashi Honda* More articles by this author Ryutaro Shimizu More articles by this author Shogo Teraoka More articles by this author Ryoma Nishikawa More articles by this author Yusuke Kimura More articles by this author Panagiota Tsounapi More articles by this author Hideto Iwamoto More articles by this author Shuichi Morizane More articles by this author Katsuya Hikita More articles by this author Atsushi Takenaka More articles by this author Expand All Advertisement PDF downloadLoading ...