1
|
Kim G, Kim H, Jang IS. Trichloroethanol, an active metabolite of chloral hydrate, modulates tetrodotoxin-resistant Na + channels in rat nociceptive neurons. BMC Anesthesiol 2023; 23:145. [PMID: 37120567 PMCID: PMC10148498 DOI: 10.1186/s12871-023-02105-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Accepted: 04/22/2023] [Indexed: 05/01/2023] Open
Abstract
BACKGROUND Chloral hydrate is a sedative-hypnotic drug widely used for relieving fear and anxiety in pediatric patients. However, mechanisms underlying the chloral hydrate-mediated analgesic action remain unexplored. Therefore, we investigated the effect of 2',2',2'-trichloroethanol (TCE), the active metabolite of chloral hydrate, on tetrodotoxin-resistant (TTX-R) Na+ channels expressed in nociceptive sensory neurons. METHODS The TTX-R Na+ current (INa) was recorded from acutely isolated rat trigeminal ganglion neurons using the whole-cell patch-clamp technique. RESULTS Trichloroethanol decreased the peak amplitude of transient TTX-R INa in a concentration-dependent manner and potently inhibited persistent components of transient TTX-R INa and slow voltage-ramp-induced INa at clinically relevant concentrations. Trichloroethanol exerted multiple effects on various properties of TTX-R Na+ channels; it (1) induced a hyperpolarizing shift on the steady-state fast inactivation relationship, (2) increased use-dependent inhibition, (3) accelerated the onset of inactivation, and (4) retarded the recovery of inactivated TTX-R Na+ channels. Under current-clamp conditions, TCE increased the threshold for the generation of action potentials, as well as decreased the number of action potentials elicited by depolarizing current stimuli. CONCLUSIONS Our findings suggest that chloral hydrate, through its active metabolite TCE, inhibits TTX-R INa and modulates various properties of these channels, resulting in the decreased excitability of nociceptive neurons. These pharmacological characteristics provide novel insights into the analgesic efficacy exerted by chloral hydrate.
Collapse
Affiliation(s)
- Gimin Kim
- Department of Pediatric Dentistry, School of Dentistry, Kyungpook National University, Daegu, 41940, Republic of Korea
| | - Hyunjung Kim
- Department of Pediatric Dentistry, School of Dentistry, Kyungpook National University, Daegu, 41940, Republic of Korea
| | - Il-Sung Jang
- Department of Pharmacology, School of Dentistry, Kyungpook National University, 2177 Dalgubeol-daero, Jung-gu, Daegu, 41940, Republic of Korea.
- Brain Science & Engineering Institute, Kyungpook National University, Daegu, 41940, Republic of Korea.
| |
Collapse
|
2
|
Contribution of tetrodotoxin-resistant persistent Na + currents to the excitability of C-type dural afferent neurons in rats. J Headache Pain 2022; 23:73. [PMID: 35764917 PMCID: PMC9238149 DOI: 10.1186/s10194-022-01443-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Accepted: 06/20/2022] [Indexed: 01/12/2023] Open
Abstract
BACKGROUND Growing evidence supports the important role of persistent sodium currents (INaP) in the neuronal excitability of various central neurons. However, the role of tetrodotoxin-resistant (TTX-R) Na+ channel-mediated INaP in the neuronal excitability of nociceptive neurons remains poorly understood. METHODS We investigated the functional role of TTX-R INaP in the excitability of C-type nociceptive dural afferent neurons, which was identified using a fluorescent dye, 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchloride (DiI), and a whole-cell patch-clamp technique. RESULTS TTX-R INaP were found in most DiI-positive neurons, but their density was proportional to neuronal size. Although the voltage dependence of TTX-R Na+ channels did not differ among DiI-positive neurons, the extent of the onset of slow inactivation, recovery from inactivation, and use-dependent inhibition of these channels was highly correlated with neuronal size and, to a great extent, the density of TTX-R INaP. In the presence of TTX, treatment with a specific INaP inhibitor, riluzole, substantially decreased the number of action potentials generated by depolarizing current injection, suggesting that TTX-R INaP are related to the excitability of dural afferent neurons. In animals treated chronically with inflammatory mediators, the density of TTX-R INaP was significantly increased, and it was difficult to inactivate TTX-R Na+ channels. CONCLUSIONS TTX-R INaP apparently contributes to the differential properties of TTX-R Na+ channels and neuronal excitability. Consequently, the selective modulation of TTX-R INaP could be, at least in part, a new approach for the treatment of migraine headaches.
Collapse
|
3
|
Kim G, Nakamura M, Cho JH, Nam S, Jang IS. Sevoflurane modulation of tetrodotoxin-resistant Na+ channels in small-sized dorsal root ganglion neurons of rats. Neuroreport 2021; 32:1335-1340. [PMID: 34718245 DOI: 10.1097/wnr.0000000000001731] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE Volatile anesthetics are widely used for general anesthesia during surgical operations. Voltage-gated Na+ channels expressed in central neurons are major targets for volatile anesthetics; but it is unclear whether these drugs modulate native tetrodotoxin-resistant (TTX-R) Na+ channels, which are involved in the development and maintenance of inflammatory pain. METHODS In this study, we examined the effects of sevoflurane on TTX-R Na+ currents (INa) in acutely isolated rat dorsal root ganglion neurons, using a whole-cell patch-clamp technique. RESULTS Sevoflurane slightly potentiated the peak amplitude of transient TTX-R INa but more potently inhibited slow voltage-ramp-induced persistent INa in a concentration-dependent manner. Sevoflurane (0.86 ± 0.02 mM) (1) slightly shifted the steady-state fast inactivation relationship to hyperpolarizing ranges without affecting the voltage-activation relationship, (2) reduced the extent of use-dependent inhibition of Na+ channels, (3) accelerated the onset of inactivation and (4) delayed the recovery from inactivation of TTX-R Na+ channels. Thus, sevoflurane has diverse effects on TTX-R Na+ channels expressed in nociceptive neurons. CONCLUSIONS The present results suggest that the inhibition of persistent INa and the modulation of the voltage dependence and inactivation might be, at least in part, responsible for the analgesic effects elicited by sevoflurane.
Collapse
Affiliation(s)
| | - Michiko Nakamura
- Department of Pharmacology, School of Dentistry
- Brain Science & Engineering Institute, Kyungpook National University, Daegu, Republic of Korea
| | | | | | - Il-Sung Jang
- Department of Pharmacology, School of Dentistry
- Brain Science & Engineering Institute, Kyungpook National University, Daegu, Republic of Korea
| |
Collapse
|
4
|
Nakamura M, Jang IS. Propranolol modulation of tetrodotoxin-resistant Na + channels in dural afferent neurons. Eur J Pharmacol 2021; 910:174449. [PMID: 34454925 DOI: 10.1016/j.ejphar.2021.174449] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 08/25/2021] [Accepted: 08/25/2021] [Indexed: 10/20/2022]
Abstract
Propranolol, a representative adrenergic β-receptor antagonist, is widely used to prevent migraine attacks. Although propranolol is well known to inhibit tetrodotoxin-resistant (TTX-R) Na+ channels in cardiac myocytes, it is unclear whether the drug modulates these channels expressed in dural afferent neurons. In this study, we examined the effects of propranolol on TTX-R Na+ channels in medium-sized dural afferent neurons identified by the fluorescent dye DiI. The TTX-R Na+ currents (INa) were recorded from acutely isolated DiI-positive neurons using a whole-cell patch clamp technique under voltage-clamp conditions. Propranolol inhibited the noninactivating steady-state component more potently than the peak component of transient TTX-R INa. Propranolol also potently inhibited the slow voltage ramp-induced TTX-R INa in a concentration-dependent manner, suggesting that it preferentially inhibited the noninactivating or persistent INa in DiI-positive neurons. Propranolol had little effect on voltage dependence, but it increased the extent of the use-dependent inhibition of TTX-R Na+ channels. Propranolol also accelerated the onset of inactivation and retarded recovery from inactivation in these channels. Under current-clamp conditions, propranolol decreased the number of action potentials elicited by depolarizing current stimuli. In conclusion, the propranolol-mediated preferential inhibition of persistent INa and modulation of the inactivation kinetics of TTX-R Na+ channels might represent additional mechanisms for migraine prophylaxis.
Collapse
Affiliation(s)
- Michiko Nakamura
- Department of Pharmacology, School of Dentistry, Kyungpook National University, Daegu, 41940, Republic of Korea; Brain Science & Engineering Institute, Kyungpook National University, Daegu, 41940, Republic of Korea
| | - Il-Sung Jang
- Department of Pharmacology, School of Dentistry, Kyungpook National University, Daegu, 41940, Republic of Korea; Brain Science & Engineering Institute, Kyungpook National University, Daegu, 41940, Republic of Korea.
| |
Collapse
|
5
|
Lauxmann S, Sonnenberg L, Koch NA, Bosselmann C, Winter N, Schwarz N, Wuttke TV, Hedrich UBS, Liu Y, Lerche H, Benda J, Kegele J. Therapeutic Potential of Sodium Channel Blockers as a Targeted Therapy Approach in KCNA1-Associated Episodic Ataxia and a Comprehensive Review of the Literature. Front Neurol 2021; 12:703970. [PMID: 34566847 PMCID: PMC8459024 DOI: 10.3389/fneur.2021.703970] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2021] [Accepted: 07/23/2021] [Indexed: 11/17/2022] Open
Abstract
Introduction: Among genetic paroxysmal movement disorders, variants in ion channel coding genes constitute a major subgroup. Loss-of-function (LOF) variants in KCNA1, the gene coding for KV1.1 channels, are associated with episodic ataxia type 1 (EA1), characterized by seconds to minutes-lasting attacks including gait incoordination, limb ataxia, truncal instability, dysarthria, nystagmus, tremor, and occasionally seizures, but also persistent neuromuscular symptoms like myokymia or neuromyotonia. Standard treatment has not yet been developed, and different treatment efforts need to be systematically evaluated. Objective and Methods: Personalized therapeutic regimens tailored to disease-causing pathophysiological mechanisms may offer the specificity required to overcome limitations in therapy. Toward this aim, we (i) reviewed all available clinical reports on treatment response and functional consequences of KCNA1 variants causing EA1, (ii) examined the potential effects on neuronal excitability of all variants using a single compartment conductance-based model and set out to assess the potential of two sodium channel blockers (SCBs: carbamazepine and riluzole) to restore the identified underlying pathophysiological effects of KV1.1 channels, and (iii) provide a comprehensive review of the literature considering all types of episodic ataxia. Results: Reviewing the treatment efforts of EA1 patients revealed moderate response to acetazolamide and exhibited the strength of SCBs, especially carbamazepine, in the treatment of EA1 patients. Biophysical dysfunction of KV1.1 channels is typically based on depolarizing shifts of steady-state activation, leading to an LOF of KCNA1 variant channels. Our model predicts a lowered rheobase and an increase of the firing rate on a neuronal level. The estimated concentration dependent effects of carbamazepine and riluzole could partially restore the altered gating properties of dysfunctional variant channels. Conclusion: These data strengthen the potential of SCBs to contribute to functional compensation of dysfunctional KV1.1 channels. We propose riluzole as a new drug repurposing candidate and highlight the role of personalized approaches to develop standard care for EA1 patients. These results could have implications for clinical practice in future and highlight the need for the development of individualized and targeted therapies for episodic ataxia and genetic paroxysmal disorders in general.
Collapse
Affiliation(s)
- Stephan Lauxmann
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany
- Institute of Neurobiology, University of Tübingen, Tübingen, Germany
| | - Lukas Sonnenberg
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany
- Institute of Neurobiology, University of Tübingen, Tübingen, Germany
- Bernstein Center for Computational Neuroscience Tübingen, Tübingen, Germany
| | - Nils A. Koch
- Institute of Neurobiology, University of Tübingen, Tübingen, Germany
- Bernstein Center for Computational Neuroscience Tübingen, Tübingen, Germany
| | - Christian Bosselmann
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany
| | - Natalie Winter
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany
| | - Niklas Schwarz
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany
| | - Thomas V. Wuttke
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany
- Department of Neurosurgery, University of Tübingen, Tübingen, Germany
| | - Ulrike B. S. Hedrich
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany
| | - Yuanyuan Liu
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany
| | - Holger Lerche
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany
| | - Jan Benda
- Institute of Neurobiology, University of Tübingen, Tübingen, Germany
- Bernstein Center for Computational Neuroscience Tübingen, Tübingen, Germany
| | - Josua Kegele
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany
| |
Collapse
|
6
|
Effect of myocardial ischemic preconditioning on ischemia-reperfusion stimulation-induced activation in rat thoracic spinal cord with functional MRI. Int J Cardiol 2019; 285:59-64. [PMID: 30905517 DOI: 10.1016/j.ijcard.2019.03.025] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/29/2018] [Revised: 03/06/2019] [Accepted: 03/13/2019] [Indexed: 11/24/2022]
Abstract
BACKGROUND Myocardial ischemia and reperfusion-evoked spinal reflexes involve nociceptive signals that trigger neuronal excitation through cardiac afferents, projecting into the thoracic spinal cord. Ischemic preconditioning (IPC) involves brief episodes of sublethal ischemia and reperfusion enhances the resistance of the myocardium to subsequent ischemic insults. This study investigated the effects of IPC on ischemia-reperfusion (I/R) stimulation-induced activation in the thoracic spinal cord of rats. METHODS A new remotely controlled I/R model was established. The infarct size was determined as a percentage of area at risk (IS/AAR) and arrhythmia scores were evaluated. Non-invasive in vivo fMRI was used for signal quantitative analysis of thoracic spinal spatiotemporal. The role of IPC on the excitability of substantia gelatinosa (SG) neurons was assessed by spinal patch clamp recording technique. The altered expressions of c-Fos, SP, and CGRP in T4 segment were detected by immunohistochemical staining. RESULTS The novel I/R model was induced successfully and reliably utilized, and IPC treatment markedly reduced the myocardial infarct size. fMRI analysis revealed that IPC reduced the increased BOLD signals induced by prolonged ischemia-reperfusion. Patch clamp recording showed that IPC treatment reversed the enhanced excitability of SG neurons during I/R treatment. The results of immunofluorescent staining indicated that IPC mitigated the I/R-induced dramatic increase of c-Fos, and reduced the release of SP and CGRP in dorsal horns of spinal cord. CONCLUSIONS These results suggested that IPC suppressed neuronal activation induced by I/R stimuli in rat thoracic spinal cord using spinal cord fMRI and patch clamp recording techniques.
Collapse
|
7
|
Kang IS, Cho JH, Lee MG, Jang IS. Modulation of tetrodotoxin-resistant Na + channels by amitriptyline in dural afferent neurons. Eur J Pharmacol 2018; 838:69-77. [PMID: 30194938 DOI: 10.1016/j.ejphar.2018.09.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Revised: 09/03/2018] [Accepted: 09/04/2018] [Indexed: 10/28/2022]
Abstract
Migraine is characterized by recurrent and disabling headaches; therefore, several drugs have been widely prescribed to prevent acute migraine attacks. Amitriptyline, a tricyclic antidepressant, is among the most commonly administered. It is poorly known, however, whether amitriptyline modulates the excitability of dural afferent neurons that transmit pain signals from the dura mater. In this study, the effects of amitriptyline on tetrodotoxin-resistant (TTX-R) Na+ channels were examined in acutely isolated rat dural afferent neurons, which were identified by the fluorescent dye DiI. The TTX-R Na+ currents (INa) were recorded from medium-sized DiI-positive neurons using a whole-cell patch clamp technique. Amitriptyline (3 μM) slightly reduced the peak component of transient INa and induced a marked decrease in the steady-state component of transient TTX-R INa, as well as in the slow ramp-induced TTX-R INa. Our findings suggest that amitriptyline specifically inhibits persistent Na+ currents mediated by TTX-R Na+ channels. While amitriptyline had minor effects on voltage-activation/inactivation, it increased the extent of the use-dependent inhibition of TTX-R Na+ channels. Amitriptyline also affected the inactivation kinetics of TTX-R Na+ channels by significantly accelerating the inactivation of TTX-R Na+ channels and slowing the subsequent recovery. Amitriptyline decreased the number of action potentials by increasing the threshold for their generation. In conclusion, the amitriptyline-mediated diverse modulation of TTX-R Na+ channels would be, at least in part, responsible for its prophylactic efficacy for migraine attacks.
Collapse
Affiliation(s)
- In-Sik Kang
- Department of Pharmacology, School of Dentistry, Kyungpook National University, Daegu 41940, Republic of Korea
| | - Jin-Hwa Cho
- Department of Pharmacology, School of Dentistry, Kyungpook National University, Daegu 41940, Republic of Korea
| | - Maan-Gee Lee
- Department of Pharmacology, School of Medicine, Kyungpook National University, Daegu 41405, Republic of Korea; Brain Science & Engineering Institute, Kyungpook National University, Daegu 41940, Republic of Korea
| | - Il-Sung Jang
- Department of Pharmacology, School of Dentistry, Kyungpook National University, Daegu 41940, Republic of Korea; Brain Science & Engineering Institute, Kyungpook National University, Daegu 41940, Republic of Korea.
| |
Collapse
|
8
|
Non-blocking modulation contributes to sodium channel inhibition by a covalently attached photoreactive riluzole analog. Sci Rep 2018; 8:8110. [PMID: 29802266 PMCID: PMC5970139 DOI: 10.1038/s41598-018-26444-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Accepted: 05/04/2018] [Indexed: 11/08/2022] Open
Abstract
Sodium channel inhibitor drugs decrease pathological hyperactivity in various diseases including pain syndromes, myotonia, arrhythmias, nerve injuries and epilepsies. Inhibiting pathological but not physiological activity, however, is a major challenge in drug development. Sodium channel inhibitors exert their effects by a dual action: they obstruct ion flow ("block"), and they alter the energetics of channel opening and closing ("modulation"). Ideal drugs would be modulators without blocking effect, because modulation is inherently activity-dependent, therefore selective for pathological hyperactivity. Can block and modulation be separated? It has been difficult to tell, because the effect of modulation is obscured by conformation-dependent association/dissociation of the drug. To eliminate dynamic association/dissociation, we used a photoreactive riluzole analog which could be covalently bound to the channel; and found, unexpectedly, that drug-bound channels could still conduct ions, although with modulated gating. The finding that non-blocking modulation is possible, may open a novel avenue for drug development because non-blocking modulators could be more specific in treating hyperactivity-linked diseases.
Collapse
|
9
|
Nagoya K, Nakamura S, Ikeda K, Onimaru H, Yoshida A, Nakayama K, Mochizuki A, Kiyomoto M, Sato F, Kawakami K, Takahashi K, Inoue T. Distinctive features of Phox2b-expressing neurons in the rat reticular formation dorsal to the trigeminal motor nucleus. Neuroscience 2017; 358:211-226. [PMID: 28673717 DOI: 10.1016/j.neuroscience.2017.06.035] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2017] [Revised: 06/03/2017] [Accepted: 06/21/2017] [Indexed: 10/19/2022]
Abstract
Phox2b encodes a paired-like homeodomain-containing transcription factor essential for development of the autonomic nervous system. Phox2b-expressing (Phox2b+) neurons are present in the reticular formation dorsal to the trigeminal motor nucleus (RdV) as well as the nucleus of the solitary tract and parafacial respiratory group. However, the nature of Phox2b+ RdV neurons is still unclear. We investigated the physiological and morphological properties of Phox2b+ RdV neurons using postnatal day 2-7 transgenic rats expressing yellow fluorescent protein under the control of Phox2b. Almost all of Phox2b+ RdV neurons were glutamatergic, whereas Phox2b-negative (Phox2b-) RdV neurons consisted of a few glutamatergic, many GABAergic, and many glycinergic neurons. The majority (48/56) of Phox2b+ neurons showed low-frequency firing (LF), while most of Phox2b- neurons (35/42) exhibited high-frequency firing (HF) in response to intracellularly injected currents. All, but one, Phox2b+ neurons (55/56) did not fire spontaneously, whereas three-fourths of the Phox2b- neurons (31/42) were spontaneously active. K+ channel and persistent Na+ current blockers affected the firing of LF and HF neurons. The majority of Phox2b+ (35/46) and half of the Phox2b- neurons (19/40) did not respond to stimulations of the mesencephalic trigeminal nucleus, the trigeminal tract, and the principal sensory trigeminal nucleus. Biocytin labeling revealed that about half of the Phox2b+ (5/12) and Phox2b- RdV neurons (5/10) send their axons to the trigeminal motor nucleus. These results suggest that Phox2b+ RdV neurons have distinct neurotransmitter phenotypes and firing properties from Phox2b- RdV neurons and might play important roles in feeding-related functions including suckling and possibly mastication.
Collapse
Affiliation(s)
- Kouta Nagoya
- Department of Oral Physiology, Showa University School of Dentistry, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan; Division of Oral Rehabilitation Medicine, Department of Special Needs Dentistry, Showa University School of Dentistry, 2-2-1 Kitasenzoku, Ota-ku, Tokyo 145-8515, Japan
| | - Shiro Nakamura
- Department of Oral Physiology, Showa University School of Dentistry, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan.
| | - Keiko Ikeda
- Division of Biology, Hyogo College of Medicine, 1-1 Mukogawa-cho, Nishinomiya, Hyogo 663-8501, Japan
| | - Hiroshi Onimaru
- Department of Physiology, Showa University School of Medicine, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan
| | - Atsushi Yoshida
- Department of Oral Anatomy and Neurobiology, Osaka University Graduate School of Dentistry, 1-8, Yamada-Oka, Suita, Osaka 565-0871, Japan
| | - Kiyomi Nakayama
- Department of Oral Physiology, Showa University School of Dentistry, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan
| | - Ayako Mochizuki
- Department of Oral Physiology, Showa University School of Dentistry, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan
| | - Masaaki Kiyomoto
- Department of Oral Physiology, Showa University School of Dentistry, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan
| | - Fumihiko Sato
- Department of Oral Anatomy and Neurobiology, Osaka University Graduate School of Dentistry, 1-8, Yamada-Oka, Suita, Osaka 565-0871, Japan
| | - Kiyoshi Kawakami
- Division of Biology, Center for Molecular Medicine, Jichi Medical University, 3311-1 Yakushiji, Shimotsuke, Tochigi 329-0498, Japan
| | - Koji Takahashi
- Division of Oral Rehabilitation Medicine, Department of Special Needs Dentistry, Showa University School of Dentistry, 2-2-1 Kitasenzoku, Ota-ku, Tokyo 145-8515, Japan
| | - Tomio Inoue
- Department of Oral Physiology, Showa University School of Dentistry, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan
| |
Collapse
|