MP03-10 BRAIN α7 NICOTINIC ACETYLCHOLINE RECEPTORS SUPPRESS THE RAT MICTURITION REFLEX VIA BRAIN HYDROGEN SULFIDE

Abstract

You have accessJournal of UrologyCME1 Apr 2023MP03-10 BRAIN α7 NICOTINIC ACETYLCHOLINE RECEPTORS SUPPRESS THE RAT MICTURITION REFLEX VIA BRAIN HYDROGEN SULFIDE Nobutaka Shimizu, Takahiro Shimizu, Shogo Shimizu, Youichirou Higashi, Suo Zou, Hideo Fukuhara, Takashi Karashima, Keiji Inoue, and Motoaki Saito Nobutaka ShimizuNobutaka Shimizu More articles by this author , Takahiro ShimizuTakahiro Shimizu More articles by this author , Shogo ShimizuShogo Shimizu More articles by this author , Youichirou HigashiYouichirou Higashi More articles by this author , Suo ZouSuo Zou More articles by this author , Hideo FukuharaHideo Fukuhara More articles by this author , Takashi KarashimaTakashi Karashima More articles by this author , Keiji InoueKeiji Inoue More articles by this author , and Motoaki SaitoMotoaki Saito More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003214.10AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: We previously reported that brain α7 nicotinic acetylcholine receptors (α7 nAChRs) and brain hydrogen sulfide (H2S) suppressed the rat micturition reflex via brain GABA receptors. However, it is unclear how the brain α7 nAChRs and brain H2S are related to each other in regulation of the micturition reflex. In this study, we examined whether brain H2S is involved in the suppression of micturition induced by stimulation of brain α7 nAChR. METHODS: Urethane anesthetized (0.8 g/kg, ip) male Wistar rats (350-420 g) were used. A catheter was inserted into the bladder to perform continuous cystometry (12 ml/h saline infusion). We examined effects of intracerebroventricularly (icv) pretreated GYY4137 (GYY, H2S donor, 1 or 3 nmol/rat) or AOAA (non-selective inhibitor of H2S synthesis, 3 or 10 μg/rat) on PHA568487 (PHA, α7 nAChR agonist, 0.3 or 1 nmol/rat, icv)-induced intercontraction intervals (ICI) prolongation. Continuous cystometry and evaluation of ICI and maximal voiding pressure (MVP) was started 120 min after the surgery and the first icv administration was performed 60 min after starting cystometry. RESULTS: PHA at a lower dose (0.3 nmol/rat) showed no significant effect on ICI, while under pretreatment with GYY, PHA (0.3 nmol/rat) significantly prolonged ICI even at a lower dose (Figure 1). PHA at a higher dose (1 nmol/rat) induced ICI prolongation and the PHA-induced prolongation was significantly suppressed by AOAA (Figure 2). The AOAA-induced suppression of the PHA-induced ICI prolongation was cancelled by supplementation of brain H2S via GYY (Figure 3). PHA at each dose showed no effect on MVP (data not shown). CONCLUSIONS: Brain α7 nAChRs suppressed the rat micturition reflex via brain H2S, therefore, brain α7 nAChRs and H2S might be new therapeutic targets for neurogenic bladder overactivity. Source of Funding: Smoking Research Foundation in Japan, KAKENHI (#20K07827), The Kochi Medical School Hospital President’s Discretionary Grant © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e25 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Nobutaka Shimizu More articles by this author Takahiro Shimizu More articles by this author Shogo Shimizu More articles by this author Youichirou Higashi More articles by this author Suo Zou More articles by this author Hideo Fukuhara More articles by this author Takashi Karashima More articles by this author Keiji Inoue More articles by this author Motoaki Saito More articles by this author Expand All Advertisement PDF downloadLoading ...