title: 5-HT(3) receptor expression in the mouse vestibular ganglion.
abstract: The 5-hydroxytryptamine type 3 (5-HT3) receptor is a ligand-gated ion channel and a member of the Cys-loop family of receptors. Previous studies have shown 5-HT3 receptor expression in various neural cells of the central and peripheral nervous systems. Although the function and distribution of the 5-HT3 receptor has been well established, its role in the inner ear is still poorly understood. Moreover, no study has yet determined its localization and function in the peripheral vestibular nervous system. In the present study, we reveal mRNA expression of both 5-HT3A and 5-HT3B receptor subunits in the mouse vestibular ganglion (VG) by RT-PCR and in situ hybridization (ISH). We also show by ISH that 5-HT3 receptor mRNA is only expressed in the VG (superior and inferior division) in the peripheral vestibular nervous system. Moreover, we performed Ca(2+) imaging to determine whether functional 5-HT3 receptors are present in the mouse VG, using a selective 5-HT3 receptor agonist, SR57227A. In wild mice, 32% of VG neurons responded to the agonist, whereas there was no response in 5-HT3A receptor knockout mice. These results indicate that VG cells express functional 5-HT3 receptor channels and might play a modulatory role in the peripheral vestibular nervous system.
authors: Department of Otorhinolaryngology - Head and Neck Surgery, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan; Department of Neuroscience and Cell Biology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan.
authors: Yasumitsu
authors: Y
authors: Takimoto
authors: Department of Neuroscience and Cell Biology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan. Electronic address: ishida@anat1.med.osaka-u.ac.jp.
authors: Yusuke
authors: Y
authors: Ishida
authors: Department of Neuroscience and Cell Biology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan.
authors: Yukiko
authors: Y
authors: Nakamura
authors: Department of Otorhinolaryngology - Head and Neck Surgery, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan; Department of Neuroscience and Cell Biology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan.
authors: Takefumi
authors: T
authors: Kamakura
authors: Department of Neuroscience and Cell Biology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan.
authors: Takahiro
authors: T
authors: Yamada
authors: Department of Neuroscience and Cell Biology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan.
authors: Makoto
authors: M
authors: Kondo
authors: Department of Otorhinolaryngology - Head and Neck Surgery, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan.
authors: Tadashi
authors: T
authors: Kitahara
authors: Department of Otorhinolaryngology - Head and Neck Surgery, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan.
authors: Atsuhiko
authors: A
authors: Uno
authors: Department of Otorhinolaryngology - Head and Neck Surgery, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan.
authors: Takao
authors: T
authors: Imai
authors: Department of Otorhinolaryngology - Head and Neck Surgery, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan.
authors: Arata
authors: A
authors: Horii
authors: Department of Otorhinolaryngology - Head and Neck Surgery, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan.
authors: Suzuyo
authors: S
authors: Okazaki
authors: Department of Otorhinolaryngology - Head and Neck Surgery, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan.
authors: Suetaka
authors: S
authors: Nishiike
authors: Department of Otorhinolaryngology - Head and Neck Surgery, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan.
authors: Hidenori
authors: H
authors: Inohara
authors: Department of Neuroscience and Cell Biology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan.
authors: Shoichi
authors: S
authors: Shimada
mesh_terms: D000818:Animals; D002118:Calcium / Q000378:metabolism; D048429:Cell Size; D002478:Cells, Cultured; D017950:Ganglia, Sensory / Q000187:drug effects / Q000378:metabolism*; D017404:In Situ Hybridization, Fluorescence; D008297:Male; D008564:Membrane Potentials / Q000187:drug effects; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D009474:Neurons / Q000187:drug effects / Q000378:metabolism*; D061848:Optical Imaging; D010880:Piperidines / Q000494:pharmacology; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction; D044406:Receptors, Serotonin, 5-HT3 / Q000235:genetics / Q000378:metabolism*; D058827:Serotonin 5-HT3 Receptor Agonists / Q000494:pharmacology; D013136:Spiral Ganglion / Q000187:drug effects / Q000378:metabolism
chemical_list: D010880:Piperidines; D012333:RNA, Messenger; D044406:Receptors, Serotonin, 5-HT3; D058827:Serotonin 5-HT3 Receptor Agonists; C083009:4-amino-1-(6-chloro-2-pyridyl)piperidine hydrochloride; D002118:Calcium
keywords: 5-HT; Cochlea; HTR3; In situ hybridization; Inner ear; Spiral ganglion