Updated on 2022/03/30

写真a

 
YAMADA Rei
 
Organization
Graduate School of Medicine Center for Research of Laboratory Animals and Medical Research Engineering Division for Advanced Medical Research Assistant Professor
Graduate School
Graduate School of Medicine
Undergraduate School
School of Medicine
Title
Assistant Professor
Contact information
メールアドレス

Degree 1

  1. PhD ( 2005.11   Kyoto University ) 

Research Interests 1

  1. 音源定位 両耳間時差 聴覚神経回路 シナプス 樹状突起 イオンチャネル

Research Areas 2

  1. Life Science / Basic brain sciences  / 細胞生物学

  2. Life Science / Physiology  / 聴覚情報処理

Current Research Project and SDGs 1

  1. 音源定位行動を実現する聴覚神経回路の動作原理の解明

Professional Memberships 3

  1. 日本生理学会   評議員

  2. 日本神経科学学会   一般会員

  3. 北米神経科学学会   会員

 

Papers 15

  1. Dendritic synapse geometry optimizes binaural computation in a sound localization circuit. Reviewed

    Rei Yamada and Hiroshi Kuba

    SCIENCE ADVANCES     2021.11

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    Authorship:Lead author   Language:English   Publishing type:Research paper (scientific journal)  

  2. Tonotopic Specializations in Number, Size, and Reversal Potential of GABAergic Inputs Fine-Tune Temporal Coding at Avian Cochlear Nucleus Reviewed

    Mohammed Al-Yaari, Chikao Onogi, Rei Yamada, Ryota Adachi, Daiya Kondo, Hiroshi Kuba

    JOURNAL OF NEUROSCIENCE   Vol. 41 ( 43 ) page: 8904 - 8916   2021.10

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    Authorship:Lead author   Language:English   Publishing type:Research paper (scientific journal)  

  3. Excitatory-Inhibitory Synaptic Coupling in Avian Nucleus Magnocellularis Reviewed

    JOURNAL OF NEUROSCIENCE   Vol. 40 ( 3 ) page: 619 - 631   2020.1

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    Language:English   Publishing type:Research paper (scientific journal)   Publisher:Journal of Neuroscience  

    DOI: 10.1523/JNEUROSCI.1124-19.2019

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  4. Tonotopic Differentiation of Coupling between Ca2+ and Kv1.1 Expression in Brainstem Auditory Circuit Reviewed

    Adachi Ryota, Yamada Rei, Kuba Hiroshi

    ISCIENCE   Vol. 13   page: 199 - +   2019.3

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    Language:English   Publishing type:Research paper (scientific journal)   Publisher:iScience  

    DOI: 10.1016/j.isci.2019.02.022

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  5. Tonotopic variation of the t-type Ca2+ current in avian auditory coincidence detector neurons Reviewed

    Ryota Fukaya, Rei Yamada, Hiroshi Kuba

    Journal of Neuroscience   Vol. 38 ( 2 ) page: 335 - 346   2018.1

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    Language:English   Publishing type:Research paper (scientific journal)   Publisher:Society for Neuroscience  

    Neurons in avian nucleus laminaris (NL) are binaural coincidence detectors for sound localization and are characterized by striking structural variations in dendrites and axon initial segment (AIS) according to their acoustic tuning [characteristic frequency (CF)]. T-type Ca2+ (CaT) channels regulate synaptic integration and firing behavior at these neuronal structures. However, whether or how CaT channels contribute to the signal processing in NL neurons is not known. In this study, we addressed this issue with whole-cell recording and two-photon Ca2+ imaging in brain slices of posthatch chicks of both sexes. We found that the CaT current was prominent in low-CF neurons, whereas it was almost absent in higher-CF neurons. In addition, a large Ca2+ transient occurred at the dendrites and the AIS of low-CF neurons, indicating a localization of CaT channels at these structures in the neurons. Because low-CF neurons have long dendrites, dendritic CaT channels may compensate for the attenuation of EPSPs at dendrites. Furthermore, the short distance of AIS from the soma may accelerate activation of axonal CaT current in the neurons and help EPSPs reach spike threshold. Indeed, the CaT current was activated by EPSPs and augmented the synaptic response and spike generation of the neurons. Notably, the CaT current was inactivated during repetitive inputs, and these augmenting effects predominated at the initial phase of synaptic activity. These results suggested that dendritic and axonal CaT channels increase the sensitivity to sound at its onset, which may expand the dynamic range for binaural computation in low-CF NL neurons.

    DOI: 10.1523/JNEUROSCI.2237-17.2017

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  6. Structural and Functional Plasticity at the Axon Initial Segment. Reviewed

    Yamada R, Kuba H

    Frontiers in cellular neuroscience   Vol. 10 ( OCT2016 ) page: 250   2016.10

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    Publishing type:Research paper (scientific journal)  

    DOI: 10.3389/fncel.2016.00250

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  7. Redistribution of Kv1 and Kv7 enhances neuronal excitability during structural axon initial segment plasticity Reviewed

    Hiroshi Kuba, Rei Yamada, Go Ishiguro, Ryota Adachi

    NATURE COMMUNICATIONS   Vol. 6   page: 8815   2015.11

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    Publishing type:Research paper (scientific journal)   Publisher:NATURE PUBLISHING GROUP  

    Structural plasticity of the axon initial segment (AIS), the trigger zone of neurons, is a powerful means for regulating neuronal activity. Here, we show that AIS plasticity is not limited to structural changes; it also occurs as changes in ion-channel expression, which substantially augments the efficacy of regulation. In the avian cochlear nucleus, depriving afferent inputs by removing cochlea elongated the AIS, and simultaneously switched the dominant Kv channels at the AIS from Kv1.1 to Kv7.2. Due to the slow activation kinetics of Kv7.2, the redistribution of the Kv channels reduced the shunting conductance at the elongated AIS during the initiation of action potentials and effectively enhanced the excitability of the deprived neurons. The results indicate that the functional plasticity of the AIS works cooperatively with the structural plasticity and compensates for the loss of afferent inputs to maintain the homeostasis of auditory circuits after hearing loss by cochlea removal.

    DOI: 10.1038/ncomms9815

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  8. Plasticity of the Axonal Trigger Zone Reviewed

    Ryota Adachi, Rei Yamada, Hiroshi Kuba

    NEUROSCIENTIST   Vol. 21 ( 3 ) page: 255 - 265   2015.6

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    Publishing type:Research paper (scientific journal)   Publisher:SAGE PUBLICATIONS INC  

    The axon initial segment (AIS) is a specialized axonal compartment that is involved in conversion of synaptic potentials into action potentials. Recent studies revealed that structural properties of the AIS, such as length and position relative to the soma, are differentiated in a cell-specific manner and shape signal processing of individual neurons. Moreover, these structural properties are not fixed but vary in response to prolonged changes of neuronal activity, which readjusts action potential threshold and compensates for the changes of activity, indicating that this structural plasticity of the AIS works as a homeostatic mechanism and contributes to maintain neuronal activity. Neuronal activity plays a crucial role in formation, maintenance, and refinement of neural circuits as well as in pathogenesis and/or pathophysiology of diseases. Thus, this plasticity should be a key to understand physiology and pathology of the brain.

    DOI: 10.1177/1073858414535986

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  9. The Cooperation of Sustained and Phasic Inhibitions Increases the Contrast of ITD-Tuning in Low-Frequency Neurons of the Chick Nucleus Laminaris Reviewed

    Rei Yamada, Hiroko Okuda, Hiroshi Kuba, Eri Nishino, Takahiro M. Ishii, Harunori Ohmori

    JOURNAL OF NEUROSCIENCE   Vol. 33 ( 9 ) page: 3927 - 3938   2013.2

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    Publishing type:Research paper (scientific journal)   Publisher:SOC NEUROSCIENCE  

    Neurons in the nucleus laminaris (NL) of birds detect the coincidence of binaural excitatory inputs from the nucleus magnocellularis (NM) on both sides and process the interaural time differences (ITDs) for sound localization. Sustained inhibition from the superior olivary nucleus is known to control the gain of coincidence detection, which allows the sensitivity of NL neurons to ITD tolerate strong-intensity sound. Here, we found a phasic inhibition in chicken brain slices that follows the ipsilateralNMinputs after a short time delay, sharpens coincidence detection, and may enhance ITD sensitivity in low-frequency NL neurons. GABA-positive small neurons are distributed in and near the NL. These neurons generate IPSCs in NL neurons when photoactivated by a caged glutamate compound, suggesting that these GABAergic neurons are interneurons that mediate phasic inhibition. These IPSCs have fast decay kinetics that is attributable to the alpha 1-subunit of the GABA(A) receptor, the expression of which dominates in the low-frequency region of the NL. Model simulations demonstrate that phasic IPSCs narrow the time window of coincidence detection and increase the contrast of ITD-tuning during low-level, low-frequency excitatory input. Furthermore, cooperation of the phasic and sustained inhibitions effectively increases the contrast of ITD-tuning over a wide range of excitatory input levels. We propose that the complementary interaction between phasic and sustained inhibitions is the neural mechanism that regulates ITD sensitivity for low-frequency sound in the NL.

    DOI: 10.1523/JNEUROSCI.2377-12.2013

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  10. Activation of metabotropic glutamate receptors improves the accuracy of coincidence detection by presynaptic mechanisms in the nucleus laminaris of the chick Reviewed

    Hiroko Okuda, Rei Yamada, Hiroshi Kuba, Harunori Ohmori

    JOURNAL OF PHYSIOLOGY-LONDON   Vol. 591 ( 1 ) page: 365 - 378   2013.1

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    Publishing type:Research paper (scientific journal)   Publisher:WILEY-BLACKWELL  

    Key points Interaural time difference (ITD) is a major cue for sound source localization and is processed by detecting a coincidence of bilateral excitatory postsynaptic potentials (EPSPs) in the nucleus laminaris (NL) in birds. The sharpness of coincidence detection (CD) depends on the speed and size of EPSPs. We found here a regulatory mechanism of EPSP size through the presynaptic mGluR activity. The activation of mGluRs reduced the transmitter release and extent of excitatory postsynaptic current depression during tetanic stimulation, but improved the CD. Furthermore, the activity of mGluRs and their expression were graded along the tonotopic axis and were stronger toward the low frequency neurons of NL. We proposed an idea that the presynaptic mGluRs may operate as a self-regulatory mechanism to optimize the size of EPSP and have roles in sharpening the CD. This regulatory mechanism may underlie the sound source localization particularly during a long-lasting sound in the NL. Abstract Interaural time difference (ITD) is a major cue for localizing a sound source and is processed in the nucleus laminaris (NL) in birds. Coincidence detection (CD) is a crucial step for processing ITD and critically depends on the size and time course of excitatory postsynaptic potentials (EPSPs). Here, we investigated a role of metabotropic glutamate receptors (mGluRs) in the regulation of EPSP amplitude and CD in the NL of chicks. A non-specific agonist of mGluRs ((+/-)-1-aminocyclopentane-trans-1,3-dicarboxylic acid; t-ACPD) reduced the amplitude and extent of depression of excitatory postsynaptic currents (EPSCs) during a stimulus train, while the paired pulse ratio and coefficient of variation of EPSC amplitude were increased. In contrast, the amplitudes of spontaneous EPSCs were not affected, but the frequency was reduced. Thus, the effects of t-ACPD were presynaptic and reduced the release of neurotransmitter from terminals in the NL. Expression of group II mGluRs was graded along the tonotopic axis and was stronger towards the low frequency region in the NL. Both group II (DCG-IV) and group III (l-AP4) specific agonists reduced EPSC amplitude by presynaptic mechanisms, and the reduction was larger in the low frequency region; however, we could not find any effects of group I-specific agonists on EPSCs. The reduced EPSP amplitude in DCG-IV improved CD. A specific antagonist of group II mGluRs (LY341495) increased the amplitude of both EPSCs and EPSPs and enhanced the depression during a stimulus train, indicating constitutive activation of mGluRs in the NL. These observations indicate that mGluRs may work as autoreceptors and regulate EPSP size to improve CD in the NL.

    DOI: 10.1113/jphysiol.2012.244350

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  11. Properties of dendritic filtering in auditory coincidence detector neurons of birds Reviewed

    Yamada Rei, Kuba Hiroshi, Ohmori Harunori

    JOURNAL OF PHYSIOLOGICAL SCIENCES   Vol. 63   page: S189 - S189   2013

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    Publishing type:Research paper (scientific journal)  

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  12. Sound-intensity-dependent compensation for the small interaural time difference cue for sound source localization Reviewed

    Eri Nishino, Rei Yamada, Hiroshi Kuba, Hiroyuki Hioki, Takahiro Furuta, Takeshi Kaneko, Harunori Ohmori

    JOURNAL OF NEUROSCIENCE   Vol. 28 ( 28 ) page: 7153 - 7164   2008.7

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    Language:English   Publishing type:Research paper (scientific journal)   Publisher:SOC NEUROSCIENCE  

    Interaural time difference (ITD) is a major cue for sound source localization. However, animals with small heads experience small ITDs, making ITD detection difficult, particularly for low-frequency sound. Here, we describe a sound-intensity-dependent mechanism for compensating for the small ITD cues in the coincidence detector neurons in the nucleus laminaris (NL) of the chicken aged from 3 to 29 d after hatching. The hypothesized compensation mechanisms were confirmed by simulation. In vivo single-unit recordings revealed an improved contrast of ITD tuning in low-best-frequency (< 1 kHz) NL neurons by suppressing the firing activity at the worst ITD, whereas the firing rate was increased with increasing sound intensity at the best ITD. In contrast, level-dependent suppression was so weak in the middle- and high-best-frequency (< 1 kHz) NL neurons that loud sounds led to increases in firing rate at both the best and the worst ITDs. The suppression of firing activity at the worst ITD in the low-best-frequency neurons required the activation of the superior olivary nucleus (SON) and was eliminated by electrolytic lesions of the SON. The frequency-dependent suppression reflected the dense projection from the SON to the low-frequency region of NL. Thus, the small ITD cues available in low-frequency sounds were partly compensated for by a sound-intensity-dependent inhibition from the SON.

    DOI: 10.1523/JNEUROSCI.4398-07.2008

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  13. Hyperpolarization-activated cyclic nucleotide-gated cation channels regulate auditory coincidence detection in nucleus laminaris of the chick Reviewed

    R Yamada, H Kuba, TM Ishii, H Ohmori

    JOURNAL OF NEUROSCIENCE   Vol. 25 ( 39 ) page: 8867 - 8877   2005.9

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    Language:English   Publishing type:Research paper (scientific journal)   Publisher:SOC NEUROSCIENCE  

    Coincidence detection of bilateral acoustic signals in nucleus laminaris (NL) is the first step in azimuthal sound source localization in birds. Here, we demonstrate graded expression of hyperpolarization-activated cyclic nucleotide-gated (HCN) cation channels along the tonotopic axis of NL and its role in the regulation of coincidence detection. Expression of HCN1 and HCN2, but not HCN3 or HCN4, was detected in NL. Based on measurement of both subtype mRNA and protein, HCN1 varied along the tonotopic axis and was minimal in high-characteristic frequency (CF) neurons. In contrast, HCN2 was evenly distributed. The resting conductance was larger and the steady-state activation curve of I-h was more positive in neurons of middle to low CF than those of high CF, consistent with the predominance of HCN1 channels in these neurons. Application of 8-Br-cAMP or noradrenaline generated a depolarizing shift of the I-h voltage activation curve. This shift was larger in neurons of high CF than in those of middle CF. The shift in the activation voltage of I-h depolarized the resting membrane, accelerated the EPSP time course, and significantly improved the coincidence detection in neurons of high CF, suggesting that I-h may improve the localization of sound sources.

    DOI: 10.1523/JNEUROSCI.2541-05.2005

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  14. Tonotopic specialization of auditory coincidence detection in nucleus laminaris of the chick Reviewed

    H Kuba, R Yamada, Fukui, I, H Ohmori

    JOURNAL OF NEUROSCIENCE   Vol. 25 ( 8 ) page: 1924 - 1934   2005.2

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    Language:English   Publishing type:Research paper (scientific journal)   Publisher:SOC NEUROSCIENCE  

    The interaural time difference ( ITD) is a cue for localizing a sound source along the horizontal plane and is first determined in the nucleus laminaris ( NL) in birds. Neurons in NL are tonotopically organized, such that ITDs are processed separately at each characteristic frequency ( CF). Here, we investigated the excitability and coincidence detection of neurons along the tonotopic axis in NL, using a chick brainstem slice preparation. Systematic changes with CF were observed in morphological and electrophysiological properties of NL neurons. These properties included the length of dendrites, the input capacitance, the conductance of hyperpolarization- activated current, and the EPSC time course. In contrast to these gradients, the conductance of low- threshold K+ current and the expression of Kv1.2 channel protein were maximal in the central ( middle- CF) region of NL. As a result, the middle- CF neuron had the smallest input resistance and membrane time constant, and consequently the fastest EPSP, and exhibited the most accurate coincidence detection. The specialization of middle- CF neurons as coincidence detectors may account for the high resolution of sound- source localization in the middle- frequency range observed in avians.

    DOI: 10.1523/JnEUROSCI.4428-04.2005

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  15. Evaluation of the limiting acuity of coincidence detection in nucleus laminaris of the chicken Reviewed

    H Kuba, R Yamada, H Ohmori

    JOURNAL OF PHYSIOLOGY-LONDON   Vol. 552 ( 2 ) page: 611 - 620   2003.10

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    Language:English   Publishing type:Research paper (scientific journal)   Publisher:CAMBRIDGE UNIV PRESS  

    The localization of sounds requires the detection of very brief inter-aural time differences (ITDs). In birds, ITDs are first encoded in neurons of the nucleus laminaris (NL) through the precise coincidence of binaural synaptic inputs. We examined the effects of temperature on acuity of coincidence detection in chick NL, by utilizing whole-cell and cell-attached recording techniques in brain slices while applying electrical stimuli bilaterally to axonal projections from the nucleus magnocellularis to NL. The precision of coincidence detection was measured as a time window, corresponding to the time interval that gave the half-maximum spiking probability. Acuity improved with the elevation of recording temperature, and at 40degreesC, the avian body temperature, the time window was 0.38 ms. Although all synaptic events were briefer at higher temperature, the duration of EPSPs were equivalent to or faster than that of EPSCs at 40degreesC. Activation of low-threshold K+ currents by a slight membrane depolarization during an EPSP was responsible for this EPSP acceleration. EPSPs were prolonged following inhibition of low-threshold K+ currents by dendrotoxin (40 nM) or hyperpolarization-activated cation currents by Cs+ (3 mm). The EPSP time course had a strong positive correlation with the sharpness of coincidence detection. The limiting value of the time window (0.16 ms), calculated from the estimated EPSP time course, was narrow enough to explain the acuity of ITD detection at NL in vivo.

    DOI: 10.1113/jphysiol.2003.041574

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Books 1

  1. Frequency dependent Specialization for processing binaural auditory cues in avian sound localization circuits. Reviewed International journal

    Advances in Sound Localization( Role: Joint author)

    Intech  2011.4  ( ISBN:978-953-307-224-1

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    Language:English Book type:Scholarly book

    DOI: 10.5772/597

Presentations 5

  1. トリ蝸牛神経核における入力周波数に応じた抑制シナプスの調節

    山田 玲

    第99回日本生理学会大会  2022.3.16 

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    Event date: 2022.3

    Language:English   Presentation type:Oral presentation (general)  

  2. トリ蝸牛神経核における周波数領域ごとの抑制性シナプスの違いとその意義

    山田 玲

    第68回中部日本生理学会  2021.10.15 

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    Event date: 2021.10

    Language:Japanese   Presentation type:Oral presentation (general)  

  3. Dendritic synapse clustering facilitates interaural time difference coding for low frequency sound.

    Rei Yamada

    The 97th annual Meeting of the Physiological Society of Japan  2020.3.18 

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    Event date: 2020.3

    Language:English   Presentation type:Oral presentation (general)  

  4. トリ蝸牛神経核シナプスにおけるSrcキナーゼの機能

    山田 玲

    生理学研究所研究会「ミクロからマクロに至る脳の構造と機能のダイナミクス」  2019.11.8  生理学研究所

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    Event date: 2019.11

    Language:Japanese   Presentation type:Oral presentation (general)  

  5. 音源定位回路におけるシナプス分布の入力周波数依存的制御 Invited

    山田 玲

    生理学研究所研究会「神経回路の構築から機能発現に至る統合的理解」  2018.12.4  生理学研究所

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    Event date: 2018.12

    Language:Japanese   Presentation type:Oral presentation (invited, special)  

KAKENHI (Grants-in-Aid for Scientific Research) 4

  1. Synaptic clustering regulates the auditory coincidence detection in low tuning frequency neurons.

    Grant number:16K08493  2016.4 - 2019.3

    Grant-in-Aid for Scientific Research 

    Yamada Rei

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    Authorship:Principal investigator  Grant type:Competitive

    Grant amount:\4810000 ( Direct Cost: \3700000 、 Indirect Cost:\1110000 )

    Neurons in nucleus laminaris (NL) of birds are the coincidence detector of binaural inputs and involved in processing of interaural time difference (ITD) for sound localization. NL neurons with low tuning frequency (low-CF neurons) have prominently long dendrites. However, contributions of dendrites to the ITD processing are still enigma. Previously, we found that synaptic inputs were clustered at distal dendrites of low-CF neurons. In this study, we found that voltage responses generated at distal dendrites were strongly attenuated particularly at the strong inputs. Model study revealed that the clustered inputs at distal dendrite generated large depolarization, which decreased synaptic current and increased K+ channel conductance, then increased the extent of attenuation in an intensity-dependent manner. We concluded that the synaptic clustering at distal dendrite would regulate the size of synaptic potential and maintain the ITD processing according to the input intensity.

  2. The properties of synaptic integration at the local dendrite of auditory coincidence detector neurons.

    Grant number:25460285  2013.4 - 2017.3

    Grant-in-Aid for Scientific Research 

    Yamada Rei

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    Authorship:Principal investigator  Grant type:Competitive

    Grant amount:\5070000 ( Direct Cost: \3900000 、 Indirect Cost:\1170000 )

    Neurons in nucleus laminaris (NL) of birds are the coincidence detector of binaural inputs and involved in processing of interaural time differences (ITDs). NL neurons with low tuning frequency (LF neurons) have prominently longer dendrites than the other frequency neurons have. However, how the dendrites contribute to the ITD processing is not well understood. In this study, we first analyzed the distribution of glutamate receptors along the dendrites with the focal uncaging of glutamate. We found that large currents were generated at distal dendrites of the LF neurons. As the amplitude of mEPSCs was uniform along the dendrites, the synaptic terminals might be concentrated at the distal dendrites. We recorded the voltage at the soma and found that the synaptic inputs on the distal dendrites were strongly attenuated because of the local depolarization and following activation of K+ channels. This attenuation might contribute to the intensity-dependent regulation of ITD processing.

  3. RoIes of feed-forward inhibition in auditory coincidence detection

    Grant number:21700431  2009 - 2010

    Grant-in-Aid for Scientific Research 

    YAMADA Rei

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    Authorship:Principal investigator  Grant type:Competitive

    Grant amount:\4290000 ( Direct Cost: \3300000 、 Indirect Cost:\990000 )

    Neurons in nucleus laminaris (NL) of birds detect the coincidence of binaural excitatory inputs and process interaural time differences (ITDs) for sound localization. In this study, we found a feed-forward inhibition that follows the EPSCs from ipsilateral cochlear nucleus after a short time delay (1-2 ms). These IPSCs were observed in the low frequency NL neurons and likely mediated by GABA-positive interneurons, which distributed in and near the low frequency NL region. Model simulations demonstrate that phasic IPSCs narrowed a time window of coincidence detection and increased the ITD sensitivity during a low-level of excitatory inputs. We concluded that the complementary interaction between the feed-forward and feedback inhibitions effectively increased the ITD sensitivity over a wide range of sound levels in low frequency NL neurons.

  4. 樹状突起におけるHCNチャネルの発現と、同時検出の機構解明

    Grant number:18700381  2006 - 2007

    科学研究費補助金  若手研究(B)

    山田 玲

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    Authorship:Principal investigator  Grant type:Competitive

    Grant amount:\3500000 ( Direct Cost: \3500000 )

    トリ層状核(NL)神経細胞は両側蝸牛神経核からのシナプス入力の同時検出器として働くことで両耳間時差を検出する。今回HCNチャネルがNL細胞における樹状突起の伝達特性にどのような影響を持つかを調べる目的で、樹状突起が発達しHCNチャネルの発現量も多い、低い特徴周波数(low-CF)領域の細胞を用いてパッチ記録を行った。細胞体で観察されるmEPSCは、コントロール条件では比較的均一な時間経過の分布を示すのに対して、HCNチャネルを薬理学的に阻害するとその時間経過の分布が広がり、HCNチャネルが樹状突起の伝達特性に関わっていることが確認できた。次に樹状突起を可視化した標本を用いて局所への投射線維を選択的に電気刺激したところ、細胞体で観察されるEPSPも刺激部位によらず均一な時間経過を示した。このことからHCNチャネルが樹状突起における入力の統合に寄与していることが示唆された。さらにHCNチャネルを薬理学的に阻害した時のEPSPおよび同時検出制度に対する影響を検討していく予定である。また抑制性入力についても検討したところ、low-CF細胞で観察されるmIPSCは他の領域に比べ4倍早い時間経過を持つことが分かった。また蝸牛神経核からの興奮性投射線維を電気刺激すると、low-CF細胞においてEPSCに数ms遅れてIPSCが観察された。このことは介在神経細胞による時間情報を保持したfeed-forward抑制回路が存在することを示唆する。今後は抑制性入力の性質および分布についても詳細に解析していく予定である。これらのことから、NL細胞における興奮性および抑制性シナプス入力についての詳細を明らかにし、シナプス入力の統合にHCNチャネルが具体的にどのように関わるのか、さらには樹状突起が果たす神経情報処理における具体的な役割を明らかにしたい。

 

Teaching Experience (On-campus) 8

  1. 生体の機能Ⅱ(植物機能生理学)実習

    2021

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    循環(心電図検査)

  2. ベーシックトレーニング

    2021

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    パッチクランプ実験の基本手技

  3. 生体の機能Ⅱ(植物機能生理学)講義

    2021

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    内分泌・生殖

  4. 生体の機能Ⅰ(動物機能生理学)講義

    2021

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    視覚・聴覚初期過程

  5. 生体の機能Ⅱ(植物機能生理学)実習

    2020

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    循環(心電図実習)

  6. 生体の機能Ⅱ(植物機能生理学)講義

    2020

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    内分泌・生殖

  7. 生体の機能Ⅰ(動物機能生理学)講義

    2020

     詳細を見る

    視覚・聴覚初期過程

  8. ベーシックトレーニング

    2020

     詳細を見る

    パッチクランプ実験の基本手技

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