mGluR1 enhances efferent inhibition of inner hair cells in the developing rat cochlea

Autores
Ye, Zhanlei; Goutman, Juan Diego; Pyott, Sonja J.; Glowatzki, Elisabeth
Año de publicación
2017
Idioma
inglés
Tipo de recurso
artículo
Estado
versión publicada
Descripción
Key points: Spontaneous activity of the sensory inner hair cells shapes maturation of the developing ascending (afferent) auditory system before hearing begins. Just before the onset of hearing, descending (efferent) input from cholinergic neurons originating in the brainstem inhibit inner hair cell spontaneous activity and may further refine maturation. We show that agonist activation of the group I metabotropic glutamate receptor mGluR1 increases the strength of this efferent inhibition by enhancing the presynaptic release of acetylcholine. We further show that the endogenous release of glutamate from the inner hair cells may increase the strength of efferent inhibition via the activation of group I metabotropic glutamate receptors. Thus, before the onset of hearing, metabotropic glutamate signalling establishes a local negative feedback loop that is positioned to regulate inner hair cell excitability and refine maturation of the auditory system. Abstract: Just before the onset of hearing, the inner hair cells (IHCs) receive inhibitory efferent input from cholinergic medial olivocochlear (MOC) neurons originating in the brainstem. This input may serve a role in the maturation of the ascending (afferent) auditory system by inhibiting spontaneous activity of the IHCs. To investigate the molecular mechanisms regulating these IHC efferent synapses, we combined electrical stimulation of the efferent fibres with patch clamp recordings from the IHCs to measure efferent synaptic strength. By examining evoked responses, we show that activation of metabotropic glutamate receptors (mGluRs) by general and group I-specific mGluR agonists enhances IHC efferent inhibition. This enhancement is blocked by application of a group I mGluR1-specific antagonist, indicating that enhancement of IHC efferent inhibition is mediated by group I mGluRs and specifically by mGluR1s. By comparing spontaneous and evoked responses, we show that group I mGluR agonists act presynaptically to increase neurotransmitter release without affecting postsynaptic responsiveness. Moreover, endogenous glutamate released from the IHCs also enhances IHC efferent inhibition via the activation of group I mGluRs. Finally, immunofluorescence analysis indicates that the efferent terminals are sufficiently close to IHC glutamate release sites to allow activation of mGluRs on the efferent terminals by glutamate spillover. Together, these results suggest that glutamate released from the IHCs activates group I mGluRs (mGluR1s), probably present on the efferent terminals, which, in turn, enhances release of acetylcholine and inhibition of the IHCs. Thus, mGluRs establish a local negative feedback loop positioned to regulate IHC activity and maturation of the ascending auditory system in the developing cochlea.
Fil: Ye, Zhanlei. Harvard University; Estados Unidos
Fil: Goutman, Juan Diego. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular "Dr. Héctor N. Torres"; Argentina
Fil: Pyott, Sonja J.. University Medical Center Groningen; Países Bajos
Fil: Glowatzki, Elisabeth. University Johns Hopkins; Estados Unidos
Materia
Glutamate
Medial Olivocochlear Nucleus
Metabotropic Glutamate Receptors
Quantal Analysis
Synapse
Nivel de accesibilidad
acceso abierto
Condiciones de uso
https://creativecommons.org/licenses/by-nc-sa/2.5/ar/
Repositorio
CONICET Digital (CONICET)
Institución
Consejo Nacional de Investigaciones Científicas y Técnicas
OAI Identificador
oai:ri.conicet.gov.ar:11336/65228

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oai_identifier_str oai:ri.conicet.gov.ar:11336/65228
network_acronym_str CONICETDig
repository_id_str 3498
network_name_str CONICET Digital (CONICET)
spelling mGluR1 enhances efferent inhibition of inner hair cells in the developing rat cochleaYe, ZhanleiGoutman, Juan DiegoPyott, Sonja J.Glowatzki, ElisabethGlutamateMedial Olivocochlear NucleusMetabotropic Glutamate ReceptorsQuantal AnalysisSynapsehttps://purl.org/becyt/ford/3.1https://purl.org/becyt/ford/3Key points: Spontaneous activity of the sensory inner hair cells shapes maturation of the developing ascending (afferent) auditory system before hearing begins. Just before the onset of hearing, descending (efferent) input from cholinergic neurons originating in the brainstem inhibit inner hair cell spontaneous activity and may further refine maturation. We show that agonist activation of the group I metabotropic glutamate receptor mGluR1 increases the strength of this efferent inhibition by enhancing the presynaptic release of acetylcholine. We further show that the endogenous release of glutamate from the inner hair cells may increase the strength of efferent inhibition via the activation of group I metabotropic glutamate receptors. Thus, before the onset of hearing, metabotropic glutamate signalling establishes a local negative feedback loop that is positioned to regulate inner hair cell excitability and refine maturation of the auditory system. Abstract: Just before the onset of hearing, the inner hair cells (IHCs) receive inhibitory efferent input from cholinergic medial olivocochlear (MOC) neurons originating in the brainstem. This input may serve a role in the maturation of the ascending (afferent) auditory system by inhibiting spontaneous activity of the IHCs. To investigate the molecular mechanisms regulating these IHC efferent synapses, we combined electrical stimulation of the efferent fibres with patch clamp recordings from the IHCs to measure efferent synaptic strength. By examining evoked responses, we show that activation of metabotropic glutamate receptors (mGluRs) by general and group I-specific mGluR agonists enhances IHC efferent inhibition. This enhancement is blocked by application of a group I mGluR1-specific antagonist, indicating that enhancement of IHC efferent inhibition is mediated by group I mGluRs and specifically by mGluR1s. By comparing spontaneous and evoked responses, we show that group I mGluR agonists act presynaptically to increase neurotransmitter release without affecting postsynaptic responsiveness. Moreover, endogenous glutamate released from the IHCs also enhances IHC efferent inhibition via the activation of group I mGluRs. Finally, immunofluorescence analysis indicates that the efferent terminals are sufficiently close to IHC glutamate release sites to allow activation of mGluRs on the efferent terminals by glutamate spillover. Together, these results suggest that glutamate released from the IHCs activates group I mGluRs (mGluR1s), probably present on the efferent terminals, which, in turn, enhances release of acetylcholine and inhibition of the IHCs. Thus, mGluRs establish a local negative feedback loop positioned to regulate IHC activity and maturation of the ascending auditory system in the developing cochlea.Fil: Ye, Zhanlei. Harvard University; Estados UnidosFil: Goutman, Juan Diego. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular "Dr. Héctor N. Torres"; ArgentinaFil: Pyott, Sonja J.. University Medical Center Groningen; Países BajosFil: Glowatzki, Elisabeth. University Johns Hopkins; Estados UnidosWiley Blackwell Publishing, Inc2017-06-01info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersionhttp://purl.org/coar/resource_type/c_6501info:ar-repo/semantics/articuloapplication/pdfapplication/pdfhttp://hdl.handle.net/11336/65228Ye, Zhanlei; Goutman, Juan Diego; Pyott, Sonja J.; Glowatzki, Elisabeth; mGluR1 enhances efferent inhibition of inner hair cells in the developing rat cochlea; Wiley Blackwell Publishing, Inc; The Journal Of Physiology; 595; 11; 1-6-2017; 3483-34950022-3751CONICET DigitalCONICETenginfo:eu-repo/semantics/altIdentifier/doi/10.1113/JP272604info:eu-repo/semantics/altIdentifier/url/https://physoc.onlinelibrary.wiley.com/doi/full/10.1113/JP272604info:eu-repo/semantics/altIdentifier/url/https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5451706/info:eu-repo/semantics/openAccesshttps://creativecommons.org/licenses/by-nc-sa/2.5/ar/reponame:CONICET Digital (CONICET)instname:Consejo Nacional de Investigaciones Científicas y Técnicas2025-09-29T09:47:05Zoai:ri.conicet.gov.ar:11336/65228instacron:CONICETInstitucionalhttp://ri.conicet.gov.ar/Organismo científico-tecnológicoNo correspondehttp://ri.conicet.gov.ar/oai/requestdasensio@conicet.gov.ar; lcarlino@conicet.gov.arArgentinaNo correspondeNo correspondeNo correspondeopendoar:34982025-09-29 09:47:05.578CONICET Digital (CONICET) - Consejo Nacional de Investigaciones Científicas y Técnicasfalse
dc.title.none.fl_str_mv mGluR1 enhances efferent inhibition of inner hair cells in the developing rat cochlea
title mGluR1 enhances efferent inhibition of inner hair cells in the developing rat cochlea
spellingShingle mGluR1 enhances efferent inhibition of inner hair cells in the developing rat cochlea
Ye, Zhanlei
Glutamate
Medial Olivocochlear Nucleus
Metabotropic Glutamate Receptors
Quantal Analysis
Synapse
title_short mGluR1 enhances efferent inhibition of inner hair cells in the developing rat cochlea
title_full mGluR1 enhances efferent inhibition of inner hair cells in the developing rat cochlea
title_fullStr mGluR1 enhances efferent inhibition of inner hair cells in the developing rat cochlea
title_full_unstemmed mGluR1 enhances efferent inhibition of inner hair cells in the developing rat cochlea
title_sort mGluR1 enhances efferent inhibition of inner hair cells in the developing rat cochlea
dc.creator.none.fl_str_mv Ye, Zhanlei
Goutman, Juan Diego
Pyott, Sonja J.
Glowatzki, Elisabeth
author Ye, Zhanlei
author_facet Ye, Zhanlei
Goutman, Juan Diego
Pyott, Sonja J.
Glowatzki, Elisabeth
author_role author
author2 Goutman, Juan Diego
Pyott, Sonja J.
Glowatzki, Elisabeth
author2_role author
author
author
dc.subject.none.fl_str_mv Glutamate
Medial Olivocochlear Nucleus
Metabotropic Glutamate Receptors
Quantal Analysis
Synapse
topic Glutamate
Medial Olivocochlear Nucleus
Metabotropic Glutamate Receptors
Quantal Analysis
Synapse
purl_subject.fl_str_mv https://purl.org/becyt/ford/3.1
https://purl.org/becyt/ford/3
dc.description.none.fl_txt_mv Key points: Spontaneous activity of the sensory inner hair cells shapes maturation of the developing ascending (afferent) auditory system before hearing begins. Just before the onset of hearing, descending (efferent) input from cholinergic neurons originating in the brainstem inhibit inner hair cell spontaneous activity and may further refine maturation. We show that agonist activation of the group I metabotropic glutamate receptor mGluR1 increases the strength of this efferent inhibition by enhancing the presynaptic release of acetylcholine. We further show that the endogenous release of glutamate from the inner hair cells may increase the strength of efferent inhibition via the activation of group I metabotropic glutamate receptors. Thus, before the onset of hearing, metabotropic glutamate signalling establishes a local negative feedback loop that is positioned to regulate inner hair cell excitability and refine maturation of the auditory system. Abstract: Just before the onset of hearing, the inner hair cells (IHCs) receive inhibitory efferent input from cholinergic medial olivocochlear (MOC) neurons originating in the brainstem. This input may serve a role in the maturation of the ascending (afferent) auditory system by inhibiting spontaneous activity of the IHCs. To investigate the molecular mechanisms regulating these IHC efferent synapses, we combined electrical stimulation of the efferent fibres with patch clamp recordings from the IHCs to measure efferent synaptic strength. By examining evoked responses, we show that activation of metabotropic glutamate receptors (mGluRs) by general and group I-specific mGluR agonists enhances IHC efferent inhibition. This enhancement is blocked by application of a group I mGluR1-specific antagonist, indicating that enhancement of IHC efferent inhibition is mediated by group I mGluRs and specifically by mGluR1s. By comparing spontaneous and evoked responses, we show that group I mGluR agonists act presynaptically to increase neurotransmitter release without affecting postsynaptic responsiveness. Moreover, endogenous glutamate released from the IHCs also enhances IHC efferent inhibition via the activation of group I mGluRs. Finally, immunofluorescence analysis indicates that the efferent terminals are sufficiently close to IHC glutamate release sites to allow activation of mGluRs on the efferent terminals by glutamate spillover. Together, these results suggest that glutamate released from the IHCs activates group I mGluRs (mGluR1s), probably present on the efferent terminals, which, in turn, enhances release of acetylcholine and inhibition of the IHCs. Thus, mGluRs establish a local negative feedback loop positioned to regulate IHC activity and maturation of the ascending auditory system in the developing cochlea.
Fil: Ye, Zhanlei. Harvard University; Estados Unidos
Fil: Goutman, Juan Diego. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular "Dr. Héctor N. Torres"; Argentina
Fil: Pyott, Sonja J.. University Medical Center Groningen; Países Bajos
Fil: Glowatzki, Elisabeth. University Johns Hopkins; Estados Unidos
description Key points: Spontaneous activity of the sensory inner hair cells shapes maturation of the developing ascending (afferent) auditory system before hearing begins. Just before the onset of hearing, descending (efferent) input from cholinergic neurons originating in the brainstem inhibit inner hair cell spontaneous activity and may further refine maturation. We show that agonist activation of the group I metabotropic glutamate receptor mGluR1 increases the strength of this efferent inhibition by enhancing the presynaptic release of acetylcholine. We further show that the endogenous release of glutamate from the inner hair cells may increase the strength of efferent inhibition via the activation of group I metabotropic glutamate receptors. Thus, before the onset of hearing, metabotropic glutamate signalling establishes a local negative feedback loop that is positioned to regulate inner hair cell excitability and refine maturation of the auditory system. Abstract: Just before the onset of hearing, the inner hair cells (IHCs) receive inhibitory efferent input from cholinergic medial olivocochlear (MOC) neurons originating in the brainstem. This input may serve a role in the maturation of the ascending (afferent) auditory system by inhibiting spontaneous activity of the IHCs. To investigate the molecular mechanisms regulating these IHC efferent synapses, we combined electrical stimulation of the efferent fibres with patch clamp recordings from the IHCs to measure efferent synaptic strength. By examining evoked responses, we show that activation of metabotropic glutamate receptors (mGluRs) by general and group I-specific mGluR agonists enhances IHC efferent inhibition. This enhancement is blocked by application of a group I mGluR1-specific antagonist, indicating that enhancement of IHC efferent inhibition is mediated by group I mGluRs and specifically by mGluR1s. By comparing spontaneous and evoked responses, we show that group I mGluR agonists act presynaptically to increase neurotransmitter release without affecting postsynaptic responsiveness. Moreover, endogenous glutamate released from the IHCs also enhances IHC efferent inhibition via the activation of group I mGluRs. Finally, immunofluorescence analysis indicates that the efferent terminals are sufficiently close to IHC glutamate release sites to allow activation of mGluRs on the efferent terminals by glutamate spillover. Together, these results suggest that glutamate released from the IHCs activates group I mGluRs (mGluR1s), probably present on the efferent terminals, which, in turn, enhances release of acetylcholine and inhibition of the IHCs. Thus, mGluRs establish a local negative feedback loop positioned to regulate IHC activity and maturation of the ascending auditory system in the developing cochlea.
publishDate 2017
dc.date.none.fl_str_mv 2017-06-01
dc.type.none.fl_str_mv info:eu-repo/semantics/article
info:eu-repo/semantics/publishedVersion
http://purl.org/coar/resource_type/c_6501
info:ar-repo/semantics/articulo
format article
status_str publishedVersion
dc.identifier.none.fl_str_mv http://hdl.handle.net/11336/65228
Ye, Zhanlei; Goutman, Juan Diego; Pyott, Sonja J.; Glowatzki, Elisabeth; mGluR1 enhances efferent inhibition of inner hair cells in the developing rat cochlea; Wiley Blackwell Publishing, Inc; The Journal Of Physiology; 595; 11; 1-6-2017; 3483-3495
0022-3751
CONICET Digital
CONICET
url http://hdl.handle.net/11336/65228
identifier_str_mv Ye, Zhanlei; Goutman, Juan Diego; Pyott, Sonja J.; Glowatzki, Elisabeth; mGluR1 enhances efferent inhibition of inner hair cells in the developing rat cochlea; Wiley Blackwell Publishing, Inc; The Journal Of Physiology; 595; 11; 1-6-2017; 3483-3495
0022-3751
CONICET Digital
CONICET
dc.language.none.fl_str_mv eng
language eng
dc.relation.none.fl_str_mv info:eu-repo/semantics/altIdentifier/doi/10.1113/JP272604
info:eu-repo/semantics/altIdentifier/url/https://physoc.onlinelibrary.wiley.com/doi/full/10.1113/JP272604
info:eu-repo/semantics/altIdentifier/url/https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5451706/
dc.rights.none.fl_str_mv info:eu-repo/semantics/openAccess
https://creativecommons.org/licenses/by-nc-sa/2.5/ar/
eu_rights_str_mv openAccess
rights_invalid_str_mv https://creativecommons.org/licenses/by-nc-sa/2.5/ar/
dc.format.none.fl_str_mv application/pdf
application/pdf
dc.publisher.none.fl_str_mv Wiley Blackwell Publishing, Inc
publisher.none.fl_str_mv Wiley Blackwell Publishing, Inc
dc.source.none.fl_str_mv reponame:CONICET Digital (CONICET)
instname:Consejo Nacional de Investigaciones Científicas y Técnicas
reponame_str CONICET Digital (CONICET)
collection CONICET Digital (CONICET)
instname_str Consejo Nacional de Investigaciones Científicas y Técnicas
repository.name.fl_str_mv CONICET Digital (CONICET) - Consejo Nacional de Investigaciones Científicas y Técnicas
repository.mail.fl_str_mv dasensio@conicet.gov.ar; lcarlino@conicet.gov.ar
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