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Hong J, Dai P, Liang H, Sun G, Qi W, Bi Y. Extrasynaptic distribution of NMDA receptors in cochlear inner hair cell afferent signaling complex. J Chem Neuroanat 2024; 137:102417. [PMID: 38570170 DOI: 10.1016/j.jchemneu.2024.102417] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2024] [Revised: 03/30/2024] [Accepted: 03/30/2024] [Indexed: 04/05/2024]
Abstract
OBJECTIVE The distribution and role of NMDA receptors is unclear in the afferent signaling complex of the cochlea. The present study aimed to examine the distribution of NMDA receptors in cochlear afferent signaling complex of the adult mouse, and their relationship with ribbon synapses of inner hair cells (IHCs) and GABAergic efferent terminals of the lateral olivocochlear (LOC). METHODS Immunofluorescence staining in combination with confocal microscopy was used to investigate the distribution of glutamatergic NMDA and AMPA receptors in afferent terminals of SGNs, and their relationship with ribbon synapses of IHCs and GABAergic efferent terminals of LOC. RESULTS Terminals with AMPA receptors along with Ribbons of IHC formed afferent synapses in the basal pole of IHCs, and those with NMDA receptors were mainly distributed longitudinally in the IHCs nuclei region. Significant difference was found in the distribution of NMDA and AMPA receptors in IHC afferent signaling complex (P<0.05). Some GABAergic terminals colocalized with NMDA receptors at the IHC nucleus region (P>0.05). CONCLUSION There is significant difference in the distribution of NMDA and AMPA receptors in cochlear afferent signaling complex. NMDA receptors are present in the extra-synaptic region of ribbon synapses of IHCs, and they are related to GABA efferent terminals of the afferent signaling complex.
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Affiliation(s)
- Juan Hong
- Department of Otorhinolaryngology, Huashan Hospital of Fudan University, Shanghai 200040, China.
| | - Peidong Dai
- ENT Institute, Eye & ENT Hospital of Fudan University; NHC Hearing Medicine Key Laboratory (Fudan University), Shanghai 200031, China
| | - Huazheng Liang
- Monash Suzhou Research Institute, Suzhou Industrial Park, Jiangsu, China
| | - Guangbin Sun
- Department of Otorhinolaryngology, Huashan Hospital of Fudan University, Shanghai 200040, China
| | - Weidong Qi
- Department of Otorhinolaryngology, Huashan Hospital of Fudan University, Shanghai 200040, China
| | - Yong Bi
- Department of Neurology, Shanghai University of Medicine & Health Sciences Affiliated Zhoupu Hospital, Shanghai 201318, China.
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2
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Drummond PD, Finch PM. Auditory disturbances in patients with complex regional pain syndrome. Pain 2023; 164:804-810. [PMID: 36036917 DOI: 10.1097/j.pain.0000000000002766] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Accepted: 07/11/2022] [Indexed: 11/26/2022]
Abstract
ABSTRACT Complex regional pain syndrome (CRPS) is often associated with reduced sound tolerance (hyperacusis) on the affected side, but the mechanism of this symptom is unclear. As compensatory increases in central auditory activity after cochlear injury may trigger hyperacusis, hearing and discomfort thresholds to pure tones (250, 500, 1000, 2000, 3000, 4000, 6000, and 8000 Hz) were assessed in 34 patients with CRPS and 26 pain-free controls. In addition, in 31 patients and 17 controls, auditory-evoked potentials to click stimuli (0.08 ms duration, 6 Hz, 60 dB above the hearing threshold) were averaged across 2000 trials for each ear. Auditory discomfort thresholds were lower at several pitches on the CRPS-affected than contralateral side and lower at all pitches on the affected side than in controls. However, ipsilateral hyperacusis was not associated with psychophysical or physiological signs of cochlear damage. Instead, neural activity in the ipsilateral brainstem and midbrain was greater when repetitive click stimuli were presented on the affected than contralateral side and greater bilaterally than in controls. In addition, click-evoked potentials, reflecting thalamo-cortical signal transfer and early cortical processing, were greater contralaterally in patients than controls. Together, these findings suggest that hyperacusis originates in the ipsilateral brainstem and midbrain rather than the peripheral auditory apparatus of patients with CRPS. Failure of processes that jointly modulate afferent auditory signalling and pain (eg, inhibitory influences stemming from the locus coeruleus) could contribute to ipsilateral hyperacusis in CRPS.
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Affiliation(s)
- Peter D Drummond
- Discipline of Psychology, College of Science, Health, Engineering and Education, Murdoch University, Murdoch, Australia
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3
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Patil JD, Alrashid MA, Eltabbakh A, Fredericks S. The association between stress, emotional states, and tinnitus: a mini-review. Front Aging Neurosci 2023; 15:1131979. [PMID: 37207076 PMCID: PMC10188965 DOI: 10.3389/fnagi.2023.1131979] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2022] [Accepted: 04/17/2023] [Indexed: 05/21/2023] Open
Abstract
Extensive literature supporting the view of tinnitus induced stress in patients is available. However, limited evidence has been produced studying the opposite, that is, does stress cause tinnitus? The hypothalamus pituitary adrenal axis, one of the main neuroendocrine systems involved in stress response, is commonly disturbed in tinnitus patients. Patients with chronic tinnitus have been shown to develop abnormal responses to psycho-social stress, where the hypothalamus pituitary adrenal axis response is weaker and delayed, suggesting chronic stress contributes to the development of chronic tinnitus. The sympathetic branch of the autonomic nervous system also plays a major role in stress response and its chronic hyperactivity seems to be involved in developing tinnitus. Psycho-social stress has been shown to share the same probability of developing tinnitus as occupational noise and contributes to worsening tinnitus. Additionally, exposure to high stress levels and occupational noise doubles the likelihood of developing tinnitus. Interestingly, short-term stress has been shown to protect the cochlea in animals, but chronic stress exposure has negative consequences. Emotional stress also worsens pre-existing tinnitus and is identified as an important indicator of tinnitus severity. Although there is limited body of literature, stress does seem to play a vital role in the development of tinnitus. This review aims to highlight the association between stress, emotional states, and the development of tinnitus while also addressing the neural and hormonal pathways involved.
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Affiliation(s)
- Jayaditya Devpal Patil
- Department of Surgery, University Hospitals of Leicester NHS Trust, Leicester, United Kingdom
- *Correspondence: Jayaditya Devpal Patil,
| | | | - Ayah Eltabbakh
- Royal College of Surgeons in Ireland, Al Muharraq, Bahrain
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4
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Vijayakumar KA, Cho GW, Maharajan N, Jang CH. A Review on Peripheral Tinnitus, Causes, and Treatments from the Perspective of Autophagy. Exp Neurobiol 2022; 31:232-242. [PMID: 36050223 PMCID: PMC9471415 DOI: 10.5607/en22002] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Revised: 08/03/2022] [Accepted: 08/10/2022] [Indexed: 01/18/2023] Open
Abstract
Tinnitus is the perception of phantom noise without any external auditory sources. The degeneration of the function or activity of the peripheral or central auditory nervous systems is one of the causes of tinnitus. This damage has numerous causes, such as loud noise, aging, and ototoxicity. All these sources excite the cells of the auditory pathway, producing reactive oxygen species that leads to the death of sensory neural hair cells. This causes involuntary movement of the tectorial membrane, resulting in the buzzing noise characteristic of tinnitus. Autophagy is an evolutionarily conserved catabolic scavenging activity inside a cell that has evolved as a cell survival mechanism. Numerous studies have demonstrated the effect of autophagy against oxidative stress, which is one of the reasons for cell excitation. This review compiles several studies that highlight the role of autophagy in protecting sensory neural hair cells against oxidative stress-induced damage. This could facilitate the development of strategies to treat tinnitus by activating autophagy.
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Affiliation(s)
- Karthikeyan A Vijayakumar
- Department of Biology, College of Natural Science, Chosun University, Gwangju 61452, Korea.,BK21 FOUR Education Research Group for Age-Associated Disorder Control Technology, Department of Integrative Biological Science, Chosun University, Gwangju 61452, Korea
| | - Gwang-Won Cho
- Department of Biology, College of Natural Science, Chosun University, Gwangju 61452, Korea.,BK21 FOUR Education Research Group for Age-Associated Disorder Control Technology, Department of Integrative Biological Science, Chosun University, Gwangju 61452, Korea
| | - Nagarajan Maharajan
- Department of Biology, College of Natural Science, Chosun University, Gwangju 61452, Korea.,BK21 FOUR Education Research Group for Age-Associated Disorder Control Technology, Department of Integrative Biological Science, Chosun University, Gwangju 61452, Korea
| | - Chul Ho Jang
- Department of Otolaryngology, Chonnam National University Medical School, Gwangju 61469, Korea
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5
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Kitcher SR, Pederson AM, Weisz CJC. Diverse identities and sites of action of cochlear neurotransmitters. Hear Res 2021; 419:108278. [PMID: 34108087 DOI: 10.1016/j.heares.2021.108278] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Revised: 04/30/2021] [Accepted: 05/18/2021] [Indexed: 11/18/2022]
Abstract
Accurate encoding of acoustic stimuli requires temporally precise responses to sound integrated with cellular mechanisms that encode the complexity of stimuli over varying timescales and orders of magnitude of intensity. Sound in mammals is initially encoded in the cochlea, the peripheral hearing organ, which contains functionally specialized cells (including hair cells, afferent and efferent neurons, and a multitude of supporting cells) to allow faithful acoustic perception. To accomplish the demanding physiological requirements of hearing, the cochlea has developed synaptic arrangements that operate over different timescales, with varied strengths, and with the ability to adjust function in dynamic hearing conditions. Multiple neurotransmitters interact to support the precision and complexity of hearing. Here, we review the location of release, action, and function of neurotransmitters in the mammalian cochlea with an emphasis on recent work describing the complexity of signaling.
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Affiliation(s)
- Siân R Kitcher
- Section on Neuronal Circuitry, National Institute on Deafness and Other Communication Disorders, NIH, Bethesda, MD 20892, United States
| | - Alia M Pederson
- Section on Neuronal Circuitry, National Institute on Deafness and Other Communication Disorders, NIH, Bethesda, MD 20892, United States
| | - Catherine J C Weisz
- Section on Neuronal Circuitry, National Institute on Deafness and Other Communication Disorders, NIH, Bethesda, MD 20892, United States.
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6
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Abstract
Emotional stress has accompanied humans since the dawn of time and has played an essential role not only in positive selection and adaptation to an ever-changing environment, but also in the acceleration or even initiation of many illnesses. The three main somatic mechanisms induced by stress are the hypothalamus-pituitary-adrenal axis (HPA axis), the sympathetic-adreno-medullar (SAM) axis, and the immune axis. In this chapter, the stress-induced mechanisms that can affect cochlear physiology are presented and discussed in the context of tinnitus generation and auditory neurobiology. It is concluded that all of the presented mechanisms need to be further investigated. It is advised that clinical practitioners ask patients about stressful events or chronic stress preceding the tinnitus onset and measure the vital signs. Finally, taking into account that tinnitus itself acts as a stressor, the implementation of anti-stress therapies for tinnitus treatment is recommended.
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7
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Sahley TL, Anderson DJ, Hammonds MD, Chandu K, Musiek FE. Evidence for a dynorphin-mediated inner ear immune/inflammatory response and glutamate-induced neural excitotoxicity: an updated analysis. J Neurophysiol 2019; 122:1421-1460. [DOI: 10.1152/jn.00595.2018] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Acoustic overstimulation (AOS) is defined as the stressful overexposure to high-intensity sounds. AOS is a precipitating factor that leads to a glutamate (GLU)-induced Type I auditory neural excitotoxicity and an activation of an immune/inflammatory/oxidative stress response within the inner ear, often resulting in cochlear hearing loss. The dendrites of the Type I auditory neural neurons that innervate the inner hair cells (IHCs), and respond to the IHC release of the excitatory neurotransmitter GLU, are themselves directly innervated by the dynorphin (DYN)-bearing axon terminals of the descending brain stem lateral olivocochlear (LOC) system. DYNs are known to increase GLU availability, potentiate GLU excitotoxicity, and induce superoxide production. DYNs also increase the production of proinflammatory cytokines by modulating immune/inflammatory signal transduction pathways. Evidence is provided supporting the possibility that the GLU-mediated Type I auditory neural dendritic swelling, inflammation, excitotoxicity, and cochlear hearing loss that follow AOS may be part of a brain stem-activated, DYN-mediated cascade of inflammatory events subsequent to a LOC release of DYNs into the cochlea. In support of a DYN-mediated cascade of events are established investigations linking DYNs to the immune/inflammatory/excitotoxic response in other neural systems.
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Affiliation(s)
- Tony L. Sahley
- Department of Biological, Geological, and Environmental Sciences, Cleveland State University, Cleveland, Ohio
- School of Health Sciences, Cleveland State University, Cleveland, Ohio
| | - David J. Anderson
- Department of Chemistry, Cleveland State University, Cleveland, Ohio
| | | | - Karthik Chandu
- Department of Chemistry, Cleveland State University, Cleveland, Ohio
| | - Frank E. Musiek
- Department of Speech, Language, and Hearing Sciences, University of Arizona, Tucson, Arizona
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8
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Liu P, Qin D, Huang X, Chen H, Ye W, Lin X, Su J. Neurotoxicity of sodium salicylate to the spiral ganglion neurons: GABA A receptor regulates NMDA receptor by Fyn-dependent phosphorylation. J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2019; 205:469-479. [PMID: 31020389 DOI: 10.1007/s00359-019-01339-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Revised: 04/12/2019] [Accepted: 04/15/2019] [Indexed: 11/25/2022]
Abstract
The purpose of this study was to observe the regulatory effects of GABAA (γ-aminobutyric acid A) receptor on the N-methyl-D-aspartate (NMDA) receptor during excitotoxicity in spiral ganglion neurons in the rat cochlea induced by sodium salicylate (SS). Western blot illustrated SS decreased the expression of NMDA receptor 2B subunit (NR2B) surface protein through affecting GABAA receptor, but the total protein content did not significantly change. Y1472 and S1480 are important phosphorylation sites in NR2B, SS downregulated the Fyn-dependent phosphorylation of Y1472 in a manner not related to the CK2 (Casein Kinase 2) dependent phosphorylation of S1480, thus regulating the surface distribution and internalization of NMDA receptor through GABAA receptor. These results suggest that the modified pattern of dynamic balance between excitation and inhibition by coactivation of the GABAA receptor can attenuate the excitatory NMDA receptor under the action of SS, via inhibiting the Fyn-dependent phosphorylation of Y1472.
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Affiliation(s)
- Peiqiang Liu
- Department of Otolaryngology-Head and Neck Surgery, First Affiliated Hospital of Guangxi Medical University, Nanning, 530021, Guangxi, China
| | - Danxue Qin
- Department of Otolaryngology-Head and Neck Surgery, First Affiliated Hospital of Guangxi Medical University, Nanning, 530021, Guangxi, China
| | - Xi Huang
- Department of Otolaryngology-Head and Neck Surgery, First Affiliated Hospital of Guangxi Medical University, Nanning, 530021, Guangxi, China
- Department of Otolaryngology-Head and Neck Surgery, Wuhan No. 1 Hospital, Wuhan, 430022, Hubei, China
| | - Huiying Chen
- Department of Otolaryngology-Head and Neck Surgery, First Affiliated Hospital of Guangxi Medical University, Nanning, 530021, Guangxi, China
| | - Wenhua Ye
- Department of Otolaryngology-Head and Neck Surgery, First Affiliated Hospital of Guangxi Medical University, Nanning, 530021, Guangxi, China
| | - Xiaoyu Lin
- Department of Otolaryngology-Head and Neck Surgery, First Affiliated Hospital of Guangxi Medical University, Nanning, 530021, Guangxi, China
| | - Jiping Su
- Department of Otolaryngology-Head and Neck Surgery, First Affiliated Hospital of Guangxi Medical University, Nanning, 530021, Guangxi, China.
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9
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Qin D, Liu P, Chen H, Huang X, Ye W, Lin X, Wei F, Su J. Salicylate-Induced Ototoxicity of Spiral Ganglion Neurons: Ca 2+/CaMKII-Mediated Interaction Between NMDA Receptor and GABA A Receptor. Neurotox Res 2019; 35:838-847. [PMID: 30820888 DOI: 10.1007/s12640-019-0006-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Revised: 01/21/2019] [Accepted: 01/24/2019] [Indexed: 10/27/2022]
Abstract
Sodium salicylate (SS) is one of the nonsteroidal anti-inflammatory drugs and widely used in clinical practice. Therefore, we aimed to investigate the potential ototoxicity mechanism of sodium salicylate: the influence of Ca2+/calmodulin-dependent protein kinase II (Ca2+/CaMKII) in interaction between NMDA receptors (NMDAR) and GABAA receptors (GABAAR) in rat cochlear spiral ganglion neurons (SGNs). After treatment with SS, NMDA, and an NMDAR inhibitor (APV), the changes of GABAAR β3 (GABR β3) mRNA, surface and total protein, and GABAAR currents in SGNs were assessed by quantitative PCR, Western blot, and whole-cell patch clamp. Mechanistically, SS and/or NMDA increased the GABR β3 mRNA expression, while decreased GABR β3 surface protein levels and GABAAR-mediated currents. Moreover, application of SS and/or NMDA showed promotion in phosphorylation levels at S383 of GABR β3. Collectively, Ca2+ chelator (BAPTA) or Ca2+/CaMKII inhibitor (KN-93) reversed the effects of SS and/or NMDA on GABAAR. Therefore, we hypothesize that the interaction between NMDAR and GABAAR is involved in the SGNs damage induced by SS. In addition, the underlying molecular mechanism is related to Ca2+/CaMKII-mediated signaling pathway, which suggests that the interaction between calcium signal-regulated receptors mediates SS ototoxicity.
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Affiliation(s)
- Danxue Qin
- Department of Otolaryngology-Head and Neck Surgery, First Affiliated Hospital of Guangxi Medical University, Nanning, 530021, Guangxi, China
| | - Peiqiang Liu
- Department of Otolaryngology-Head and Neck Surgery, First Affiliated Hospital of Guangxi Medical University, Nanning, 530021, Guangxi, China
| | - Huiying Chen
- Department of Otolaryngology-Head and Neck Surgery, First Affiliated Hospital of Guangxi Medical University, Nanning, 530021, Guangxi, China
| | - Xi Huang
- Department of Otolaryngology-Head and Neck Surgery, First Affiliated Hospital of Guangxi Medical University, Nanning, 530021, Guangxi, China.,Department of Otolaryngology-Head and Neck Surgery, Wuhan No.1 Hospital, Wuhan, 430022, Hubei, China
| | - Wenhua Ye
- Department of Otolaryngology-Head and Neck Surgery, First Affiliated Hospital of Guangxi Medical University, Nanning, 530021, Guangxi, China
| | - Xiaoyu Lin
- Department of Otolaryngology-Head and Neck Surgery, First Affiliated Hospital of Guangxi Medical University, Nanning, 530021, Guangxi, China
| | - Fangyu Wei
- Department of Otolaryngology-Head and Neck Surgery, First Affiliated Hospital of Guangxi Medical University, Nanning, 530021, Guangxi, China
| | - Jiping Su
- Department of Otolaryngology-Head and Neck Surgery, First Affiliated Hospital of Guangxi Medical University, Nanning, 530021, Guangxi, China.
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10
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Xiong S, Song Y, Liu J, Du Y, Ding Y, Wei H, Bryan K, Ma F, Mao L. Neuroprotective effects of MK-801 on auditory cortex in salicylate-induced tinnitus: Involvement of neural activity, glutamate and ascorbate. Hear Res 2019; 375:44-52. [PMID: 30795964 DOI: 10.1016/j.heares.2019.01.021] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/23/2018] [Revised: 01/17/2019] [Accepted: 01/30/2019] [Indexed: 12/14/2022]
Abstract
Tinnitus may cause anxiety, depression, insomnia, which impair the quality of life of millions worldwide. However, the mechanism of tinnitus remains to be understood, it has been previously hypothesized that the activation of N-methyl-D-aspartate (NMDA) receptor is involved in the tinnitus processes and blockade of the NMDA receptor is regarded as a therapeutic strategy for tinnitus treatment even if the rescue treatment is still proved invalid in some cases. To demonstrate the therapeutic effect of the NMDA receptor blocker on tinnitus, we examined here the spontaneous firing rate (SFR) and the neurochemical dynamics in the auditory cortex (AC) of rats after sodium salicylate (SS) injection, which is a widely used model for tinnitus research. We also recorded their responses to MK-801 treatment. Electrophysiological studies showed that MK-801 significantly suppresses SFR in AC of rats with SS-induced tinnitus. In addition, by using a technique that combining in vivo microdialysis with an online electrochemical system (OECS) and a high-performance liquid chromatography (HPLC), we found that the levels of both glutamate and ascorbate in AC dramatically increased after SS injection and that MK-801 administration attenuated those response. Further studies found that MK-801 given at a time point of 30 min pre- or post-injection of SS were more effective than that given at a time point of 60 min post-SS injection, indicating that the time point of MK-801 intervention has a critical impact on the therapeutic effect. These findings suggest that MK-801 plays a neuroprotective role against hyperactivity during tinnitus induced by SS and that the therapeutic effect depends on the time point of MK-801 intervention, which would advance the studies on understanding of the therapeutic potential of NMDA receptor antagonist in tinnitus therapy.
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Affiliation(s)
- Shan Xiong
- Department of Otolaryngology Head and Neck Surgery, Peking University Third Hospital, Beijing, 100191, China
| | - Yu Song
- Department of Otolaryngology Head and Neck Surgery, Peking University Third Hospital, Beijing, 100191, China
| | - Junxiu Liu
- Department of Otolaryngology Head and Neck Surgery, Peking University Third Hospital, Beijing, 100191, China
| | - Yali Du
- Department of Otolaryngology Head and Neck Surgery, Peking University Third Hospital, Beijing, 100191, China
| | - Yujing Ding
- Department of Otolaryngology Head and Neck Surgery, Peking University Third Hospital, Beijing, 100191, China
| | - Huan Wei
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, Institute of Chemistry, The Chinese Academy of Sciences, Beijing, 100190, China
| | - Kevin Bryan
- Junipero Serra High School, San Mateo, CA, USA
| | - Furong Ma
- Department of Otolaryngology Head and Neck Surgery, Peking University Third Hospital, Beijing, 100191, China.
| | - Lanqun Mao
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, Institute of Chemistry, The Chinese Academy of Sciences, Beijing, 100190, China.
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11
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Wang J, Yin S, Chen H, Shi L. Noise-Induced Cochlear Synaptopathy and Ribbon Synapse Regeneration: Repair Process and Therapeutic Target. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1130:37-57. [PMID: 30915700 DOI: 10.1007/978-981-13-6123-4_3] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The synapse between the inner hair cells (IHCs) and the spiral ganglion neurons (SGNs) in mammalian cochleae is characterized as having presynaptic ribbons and therefore is called ribbon synapse. The special molecular organization is reviewed in this chapter in association with the functional feature of this synapse in signal processing. This is followed by the review on noise-induced damage to this synapse with a focus on recent reports in animal models in which the effect of brief noise exposures is observed without causing significant permanent threshold shift (PTS). In this regard, the potential mechanism of the synaptic damage by noise and the impact of this damage on hearing are summarized to clarify the concept of noise-induced hidden hearing loss, which is defined as the functional deficits in hearing without threshold elevation. A controversial issue is addressed in this review as whether the disrupted synapses can be regenerated. Moreover, the review summarizes the work of therapeutic research to protect the synapses or to promote the regeneration of the synapse after initial disruption. Lastly, several unresolved issues are raised for investigation in the future.
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Affiliation(s)
- Jian Wang
- School of Communication Science and Disorders, Dalhousie University, Halifax, NS, Canada.
| | - Shankai Yin
- Otolaryngology Research Institute, 6th Affiliated Hospital, Shanghai Jiao-Tong University, Shanghai, China
| | - Hengchao Chen
- Otolaryngology Research Institute, 6th Affiliated Hospital, Shanghai Jiao-Tong University, Shanghai, China
| | - Lijuan Shi
- Department of Physiology, Medical College of Southeast University, Nanjing, China
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12
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Haider HF, Bojić T, Ribeiro SF, Paço J, Hall DA, Szczepek AJ. Pathophysiology of Subjective Tinnitus: Triggers and Maintenance. Front Neurosci 2018; 12:866. [PMID: 30538616 PMCID: PMC6277522 DOI: 10.3389/fnins.2018.00866] [Citation(s) in RCA: 72] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2018] [Accepted: 11/06/2018] [Indexed: 01/07/2023] Open
Abstract
Tinnitus is the conscious perception of a sound without a corresponding external acoustic stimulus, usually described as a phantom perception. One of the major challenges for tinnitus research is to understand the pathophysiological mechanisms triggering and maintaining the symptoms, especially for subjective chronic tinnitus. Our objective was to synthesize the published literature in order to provide a comprehensive update on theoretical and experimental advances and to identify further research and clinical directions. We performed literature searches in three electronic databases, complemented by scanning reference lists from relevant reviews in our included records, citation searching of the included articles using Web of Science, and manual searching of the last 6 months of principal otology journals. One-hundred and thirty-two records were included in the review and the information related to peripheral and central mechanisms of tinnitus pathophysiology was collected in order to update on theories and models. A narrative synthesis examined the main themes arising from this information. Tinnitus pathophysiology is complex and multifactorial, involving the auditory and non-auditory systems. Recent theories assume the necessary involvement of extra-auditory brain regions for tinnitus to reach consciousness. Tinnitus engages multiple active dynamic and overlapping networks. We conclude that advancing knowledge concerning the origin and maintenance of specific tinnitus subtypes origin and maintenance mechanisms is of paramount importance for identifying adequate treatment.
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Affiliation(s)
- Haúla Faruk Haider
- ENT Department, Hospital Cuf Infante Santo - NOVA Medical School, Lisbon, Portugal
| | - Tijana Bojić
- Laboratory of Radiobiology and Molecular Genetics, Vinča Institute of Nuclear Sciences, University of Belgrade, Belgrade, Serbia
| | - Sara F Ribeiro
- ENT Department, Hospital Cuf Infante Santo - NOVA Medical School, Lisbon, Portugal
| | - João Paço
- ENT Department, Hospital Cuf Infante Santo - NOVA Medical School, Lisbon, Portugal
| | - Deborah A Hall
- NIHR Nottingham Biomedical Research Centre, Nottingham, United Kingdom.,Hearing Sciences, Division of Clinical Neuroscience, School of Medicine, University of Nottingham, Nottingham, United Kingdom.,Queen's Medical Centre, Nottingham University Hospitals NHS Trust, Nottingham, United Kingdom.,University of Nottingham Malaysia, Semeniyh, Malaysia
| | - Agnieszka J Szczepek
- Department of Otorhinolaryngology, Head and Neck Surgery, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany
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13
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Haider HF, Flook M, Aparicio M, Ribeiro D, Antunes M, Szczepek AJ, Hoare DJ, Fialho G, Paço JC, Caria H. Biomarkers of Presbycusis and Tinnitus in a Portuguese Older Population. Front Aging Neurosci 2017; 9:346. [PMID: 29163129 PMCID: PMC5672025 DOI: 10.3389/fnagi.2017.00346] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Accepted: 10/16/2017] [Indexed: 12/28/2022] Open
Abstract
Introduction: Presbycusis or age-related hearing loss (ARHL) is a ubiquitous health problem. It is estimated that it will affect up to 1.5 billion people by 2025. In addition, tinnitus occurs in a large majority of cases with presbycusis. Glutamate metabotropic receptor 7 (GRM7) and N-acetyltransferase 2 (NAT2) are some of the genetic markers for presbycusis. Objectives: To explore patterns of hearing loss and the role of GRM7 and NAT2 as possible markers of presbycusis and tinnitus in a Portuguese population sample. Materials and Methods: Tonal and speech audiometry, tinnitus assessment, clinical interview, and DNA samples were obtained from patients aged from 55 to 75 with or without tinnitus. GRM7 analysis was performed by qPCR. Genotyping of single nucleotide polymorphisms (SNPs) in NAT2 was performed by PCR amplification followed by Sanger sequencing or by qPCR. Results: We screened samples from 78 individuals (33 men and 45 women). T allele at GRM7 gene was the most observed (60.3% T/T and 33.3% A/T). Individuals with a T/T genotype have a higher risk for ARHL and 33% lower risk for tinnitus, compared to individuals with A/A and A/T genotype, respectively. Being a slow acetylator (53%) was the most common NAT2 phenotype, more common in men (55.8%). Intermediate acetylator was the second most common phenotype (35.9%) also more frequent in men (82.6%). Noise exposed individuals and individuals with ‘high frequency’ hearing loss seem to have a higher risk for tinnitus. Our data suggests that allele AT of GRM7 can have a statistically significant influence toward the severity of tinnitus. Conclusion: For each increasing year of age the chance of HL increases by 9%. The risk for ARHL was not significantly associated with GRM7 neither NAT2. However, we cannot conclude from our data whether the presence of T allele at GRM7 increases the odds for ARHL or whether the A allele has a protective effect. Genotype A/T at GRM7 could potentially be considered a biomarker of tinnitus severity. This is the first study evaluating the effect of GRM7 and NAT2 gene in tinnitus.
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Affiliation(s)
- Haúla F Haider
- ENT Department, Hospital Cuf Infante Santo, NOVA Medical School, Lisbon, Portugal
| | - Marisa Flook
- Deafness Research Group, BTR Unit, BioISI, Faculty of Sciences, University of Lisbon (FCUL), Lisbon, Portugal
| | | | - Diogo Ribeiro
- ENT Department, Hospital Cuf Infante Santo, NOVA Medical School, Lisbon, Portugal
| | - Marilia Antunes
- Centro de Estatística e Aplicações, Faculty of Sciences, University of Lisbon, Lisbon, Portugal
| | | | - Derek J Hoare
- NIHR Nottingham Biomedical Research Centre, Division of Clinical Neuroscience, School of Medicine, University of Nottingham, Nottingham, United Kingdom
| | - Graça Fialho
- Deafness Research Group, BTR Unit, BioISI, Faculty of Sciences, University of Lisbon (FCUL), Lisbon, Portugal
| | - João C Paço
- ENT Department, Hospital Cuf Infante Santo, NOVA Medical School, Lisbon, Portugal
| | - Helena Caria
- Deafness Research Group, BTR Unit, BioISI, Faculty of Sciences, University of Lisbon (FCUL), Lisbon, Portugal.,ESS/IPS- Biomedical Sciences Department, School of Health, Polytechnic Institute of Setubal, Setubal, Portugal
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Manohar S, Dahar K, Adler HJ, Dalian D, Salvi R. Noise-induced hearing loss: Neuropathic pain via Ntrk1 signaling. Mol Cell Neurosci 2016; 75:101-12. [PMID: 27473923 DOI: 10.1016/j.mcn.2016.07.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2015] [Revised: 06/30/2016] [Accepted: 07/25/2016] [Indexed: 12/18/2022] Open
Abstract
Severe noise-induced damage to the inner ear leads to auditory nerve fiber degeneration thereby reducing the neural input to the cochlear nucleus (CN). Paradoxically, this leads to a significant increase in spontaneous activity in the CN which has been linked to tinnitus, hyperacusis and ear pain. The biological mechanisms that lead to an increased spontaneous activity are largely unknown, but could arise from changes in glutamatergic or GABAergic neurotransmission or neuroinflammation. To test this hypothesis, we unilaterally exposed rats for 2h to a 126dB SPL narrow band noise centered at 12kHz. Hearing loss measured by auditory brainstem responses exceeded 55dB from 6 to 32kHz. The mRNA from the exposed CN was harvested at 14 or 28days post-exposure and qRT-PCR analysis was performed on 168 genes involved in neural inflammation, neuropathic pain and glutamatergic or GABAergic neurotransmission. Expression levels of mRNA of Slc17a6 and Gabrg3, involved in excitation and inhibition respectively, were significantly increased at 28days post-exposure, suggesting a possible role in the CN spontaneous hyperactivity associated with tinnitus and hyperacusis. In the pain and inflammatory array, noise exposure upregulated mRNA expression levels of four pain/inflammatory genes, Tlr2, Oprd1, Kcnq3 and Ntrk1 and decreased mRNA expression levels of two more genes, Ccl12 and Il1β. Pain/inflammatory gene expression changes via Ntrk1 signaling may induce sterile inflammation, neuropathic pain, microglial activation and migration of nerve fibers from the trigeminal, cuneate and vestibular nuclei into the CN. These changes could contribute to somatic tinnitus, hyperacusis and otalgia.
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Affiliation(s)
- Senthilvelan Manohar
- Center for Hearing & Deafness, State University of New York at Buffalo, Buffalo, NY 14214, United States.
| | - Kimberly Dahar
- Center for Hearing & Deafness, State University of New York at Buffalo, Buffalo, NY 14214, United States
| | - Henry J Adler
- Center for Hearing & Deafness, State University of New York at Buffalo, Buffalo, NY 14214, United States
| | - Ding Dalian
- Center for Hearing & Deafness, State University of New York at Buffalo, Buffalo, NY 14214, United States
| | - Richard Salvi
- Center for Hearing & Deafness, State University of New York at Buffalo, Buffalo, NY 14214, United States
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15
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Knipper M, Panford-Walsh R, Singer W, Rüttiger L, Zimmermann U. Specific synaptopathies diversify brain responses and hearing disorders: you lose the gain from early life. Cell Tissue Res 2015; 361:77-93. [PMID: 25843689 PMCID: PMC4487345 DOI: 10.1007/s00441-015-2168-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2015] [Accepted: 03/05/2015] [Indexed: 01/08/2023]
Abstract
Before hearing onset, inner hair cell (IHC) maturation proceeds under the influence of spontaneous Ca(2+) action potentials (APs). The temporal signature of the IHC Ca(2+) AP is modified through an efferent cholinergic feedback from the medial olivocochlear bundle (MOC) and drives the IHC pre- and post-synapse phenotype towards low spontaneous (spike) rate (SR), high-threshold characteristics. With sensory experience, the IHC pre- and post-synapse phenotype matures towards the instruction of low-SR, high-threshold and of high-SR, low-threshold auditory fiber characteristics. Corticosteroid feedback together with local brain-derived nerve growth factor (BDNF) and catecholaminergic neurotransmitters (dopamine) might be essential for this developmental step. In this review, we address the question of whether the control of low-SR and high-SR fiber characteristics is linked to various degrees of vulnerability of auditory fibers in the mature system. In particular, we examine several IHC synaptopathies in the context of various hearing disorders and exemplified shortfalls before and after hearing onset.
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Affiliation(s)
- Marlies Knipper
- Department of Otolaryngology, Head and Neck Surgery, Tübingen Hearing Research Center (THRC), Molecular Physiology of Hearing, University of Tübingen, Elfriede-Aulhorn-Straße 5, 72076 Tübingen, Germany
| | | | - Wibke Singer
- Department of Otolaryngology, Head and Neck Surgery, Tübingen Hearing Research Center (THRC), Molecular Physiology of Hearing, University of Tübingen, Elfriede-Aulhorn-Straße 5, 72076 Tübingen, Germany
| | - Lukas Rüttiger
- Department of Otolaryngology, Head and Neck Surgery, Tübingen Hearing Research Center (THRC), Molecular Physiology of Hearing, University of Tübingen, Elfriede-Aulhorn-Straße 5, 72076 Tübingen, Germany
| | - Ulrike Zimmermann
- Department of Otolaryngology, Head and Neck Surgery, Tübingen Hearing Research Center (THRC), Molecular Physiology of Hearing, University of Tübingen, Elfriede-Aulhorn-Straße 5, 72076 Tübingen, Germany
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16
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Sanchez J, Ghelani S, Otto-Meyer S. From development to disease: Diverse functions of NMDA-type glutamate receptors in the lower auditory pathway. Neuroscience 2015; 285:248-59. [DOI: 10.1016/j.neuroscience.2014.11.027] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2014] [Revised: 11/07/2014] [Accepted: 11/16/2014] [Indexed: 01/19/2023]
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Partial to complete suppression of unilateral noise-induced tinnitus in rats after cyclobenzaprine treatment. J Assoc Res Otolaryngol 2014; 16:263-72. [PMID: 25526855 DOI: 10.1007/s10162-014-0500-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2014] [Accepted: 11/25/2014] [Indexed: 12/24/2022] Open
Abstract
Some forms of tinnitus are believed to arise from abnormal central nervous system activity following a single or repeated noise exposure, for which there are no widely accepted pharmacological treatments. One central site that could be related to tinnitus awareness or modulation is the locus coeruleus, a brainstem structure associated with stress, arousal, and attention. In the present study, we evaluated the effects of cyclobenzaprine, a drug known to act on the rat locus coeruleus, on noise-induced tinnitus using Gap Prepulse Inhibition of the Acoustic Startle (GPIAS). In untreated rats, brief silent gaps presented prior to a 5-10-kHz bandpass startling stimulus produced robust GPIAS. Treatment with cyclobenzaprine alone had no effect on the ability of gaps to suppress the startle response. When animals were exposed to intense narrow-band (126 dB SPL, 16 kHz, 100 Hz BW) unilateral noise, GPIAS was significantly reduced, suggesting the presence of tinnitus. Following the noise exposure, a subset of rats that maintained a robust startle response continued to show GPIAS impairment at 6-20 kHz, 40 days post-noise, suggesting chronic tinnitus. When this subset of animals was treated with cyclobenzaprine, at a dose that had no significant effects on the startle response (0.5 mg/kg), GPIAS recovered partially or to near baseline levels at the affected frequencies. These results were consistent with the absence of tinnitus. By 48 h post-treatment, evidence of tinnitus re-emerged. Our results suggest that cyclobenzaprine was effective in transiently suppressing noise-induced tinnitus in rats.
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18
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Effects of salicylate on the inflammatory genes expression and synaptic ultrastructure in the cochlear nucleus of rats. Inflammation 2014; 37:365-73. [PMID: 24092407 DOI: 10.1007/s10753-013-9748-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Aspirin (salicylate), as a common drug that is frequently used for long-term treatment in a clinical setting, has the potential to cause reversible tinnitus. However, few reports have examined the inflammatory cytokines expression and alteration of synaptic ultrastructure in the cochlear nucleus (CN) in a rat model of tinnitus. The tinnitus-like behavior of rats were detected by the gap prepulse inhibition of acoustic startle (GPIAS) paradigm. We investigated the expression levels of the tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), N-methyl D-aspartate receptor subunit 2A (NR2A) mRNA and protein in the CN and compared synapses ultrastructure in the CN of tinnitus rats with normal ones. GPIAS showed that rats with long-term administration of salicylate were experiencing tinnitus, and the mRNA and protein expression levels of TNF-α and NR2A were up-regulated in chronic treatment groups, and they returned to baseline 14 days after cessation of treatment. Furthermore, compared to normal rats, repetitive salicylate-treated rats showed a greater number of presynaptic vesicles, thicker and longer postsynaptic densities, increased synaptic interface curvature. These data revealed that chronic salicylate administration markedly, but reversibly, induces tinnitus possibly via augmentation of the expression of TNF-α and NR2A and cause changes in synaptic ultrastructure in the CN. Long-term administration of salicylate causes neural plasticity changes at the CN level.
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19
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Song F, Li Q, Wan ZY, Zhao YJ, Huang F, Yang Q, Zhao WF, Zhang M, Chen YJ. Lamotrigine reverses masseter overactivity caused by stress maybe via Glu suppression. Physiol Behav 2014; 137:25-32. [PMID: 24955497 DOI: 10.1016/j.physbeh.2014.06.017] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2014] [Revised: 05/25/2014] [Accepted: 06/13/2014] [Indexed: 12/15/2022]
Abstract
Experimental and non-experimental stress significantly increase masseter muscle tone, which has been linked to the symptoms and pathogenesis of several stomatognathic system diseases. Until now, the mechanism underlying this phenomenon has remained unclear. The current study was performed to determine the mechanism of the stress-induced increase in masseter muscle tone and to investigate the effect of lamotrigine on this change. Animals challenged by repeated restraint stress received either saline as a vehicle or lamotrigine in doses of 20, 30 or 40 mg/kg body weight, whereas control animals received saline without stress treatment. Masseter muscle tone was assessed using electromyography. The activity of glutamate-related metabolic enzymes (glutaminase and glutamine synthetase) in the trigeminal motor nucleus was also investigated. Our results showed an interesting phenomenon: masseter muscle activity increased concurrently with the upregulation of the glutamate concentration after stress treatment. The activities of glutaminase and glutamine synthetase in the trigeminal motor nucleus were also upregulated and downregulated, respectively, when the rats were challenged by prolonged stress. The animals treated with lamotrigine at moderate and high doses had significantly decreased masseter muscle tone compared with stressed animals treated with vehicle. These results suggested that increased glutaminase activity and decreased glutamine synthetase activity increased glutamate production and decreased glutamate decomposition, causing an increase in glutamate levels in the trigeminal motor nucleus and eventually increasing masseter muscle tone. The administration of lamotrigine at doses of 30 or 40 mg/kg body weight effectively mitigated the adverse effects of stress on masseter muscle tone via inhibition of glutamate release.
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Affiliation(s)
- Fang Song
- State Key Laboratory of Military Stomatology, Department of General Dentistry & Emergency, School of Stomatology, Fourth Military Medical University, Xi'an 710032, Shaanxi, PR China
| | - Qiang Li
- State Key Laboratory of Military Stomatology, Department of General Dentistry & Emergency, School of Stomatology, Fourth Military Medical University, Xi'an 710032, Shaanxi, PR China
| | - Zhong-Yuan Wan
- Department of Orthopaedics, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, Shaanxi, PR China
| | - Ya-Juan Zhao
- State Key Laboratory of Military Stomatology, Department of General Dentistry & Emergency, School of Stomatology, Fourth Military Medical University, Xi'an 710032, Shaanxi, PR China
| | - Fei Huang
- State Key Laboratory of Military Stomatology, Department of General Dentistry & Emergency, School of Stomatology, Fourth Military Medical University, Xi'an 710032, Shaanxi, PR China; Department of Stomatology, PLA Navy General Hospital, Beijing 100048, PR China
| | - Qi Yang
- Department of Pharmacology, School of Pharmacy, Fourth Military Medical University, Xi'an 710032, Shaanxi, PR China
| | - Wen-Feng Zhao
- Department of Stomatology, General Hospital of Beijing Military Command, Dongsishitiao Road South Gate Warehouse No. 5, Beijing 100700, PR China.
| | - Min Zhang
- State Key Laboratory of Military Stomatology, Department of General Dentistry & Emergency, School of Stomatology, Fourth Military Medical University, Xi'an 710032, Shaanxi, PR China.
| | - Yong-Jin Chen
- State Key Laboratory of Military Stomatology, Department of General Dentistry & Emergency, School of Stomatology, Fourth Military Medical University, Xi'an 710032, Shaanxi, PR China.
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20
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Le Prell CG, Hughes LF, Bledsoe SC. Dynorphin release by the lateral olivocochlear efferents may inhibit auditory nerve activity: a cochlear drug delivery study. Neurosci Lett 2014; 571:17-22. [PMID: 24780562 DOI: 10.1016/j.neulet.2014.04.024] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2013] [Revised: 04/15/2014] [Accepted: 04/18/2014] [Indexed: 11/28/2022]
Abstract
Dynorphin (dyn) is suggested to excite the auditory nerve (AN) when released by the lateral olivocochlear (LOC) efferents. However, previous studies evaluated either intravenously delivered dyn-like agents, raising the potential for systemic (central) effects, or agent concentrations unlikely to be achieved via endogenous cochlear release. This study tested the hypothesis that biologically relevant increases in dyn levels in the cochlea achieved via diffusion of the drug of (-)pentazocine across the round window membrane enhances AN firing. In general, amplitude of the cochlear whole-nerve action potential (CAP) was depressed following drug application. These results suggest that dyn released by the LOC neurons would likely act as an inhibitory transmitter substance in the LOC system; neurotransmission is one of the LOC system's vast unknowns.
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Affiliation(s)
| | - Larry F Hughes
- Department of Surgery, Southern Illinois University School of Medicine, USA
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21
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Moral-Vico J, Carretero N, Pérez E, Suñol C, Lichtenstein M, Casañ-Pastor N. Dynamic electrodeposition of aminoacid-polypyrrole on aminoacid-PEDOT substrates: Conducting polymer bilayers as electrodes in neural systems. Electrochim Acta 2013. [DOI: 10.1016/j.electacta.2013.08.041] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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