Upon reaching adulthood, a marked decrease in CB- and PV-immunoreactive neurons was observed in the contralateral SOC, particularly in the medial nucleus of the trapezoid body (MNTB), although no neuronal cell death was observed. 
The medial nucleus of the trapezoid body (MNTB) receives excitatory input from giant presynaptic terminals, the calyces of Held.
In vitro studies from brain slices revealed a novel presynaptic site of glycine action in the medial nucleus of the trapezoid body (MNTB) which increases the release of the excitatory transmitter glutamate from the calyx of Held.
They also receive a prominent inhibitory, glycinergic projection from the ipsilateral medial nucleus of the trapezoid body (MNTB), which contributes to the fine-tuning of ITD analysis.
The total of medial olivocochlear (MOC) neurons was 780 (31%), mainly located in dorsomedial periolivary nucleus, medial nucleus of the trapezoid body and ventral nucleus of the trapezoid body, mainly distributed in the rostral extent of the pons, predominantly projected contralaterally.
Principal neurons of the medial nucleus of the trapezoid body (MNTB) integrate the large, excitatory inputs from anteroventral cochlear nucleus (AVCN) bushy cells with conventional inhibitory inputs to produce an inhibitory output to the lateral and medial superior olive.
We assessed the potential of using multielectrode arrays (MEAs) to investigate several physiological properties of the calyx of Held synapse in the medial nucleus of the trapezoid body of gerbil.
We investigated this representation in the medial nucleus of the trapezoid body (MNTB) of the Mongolian gerbil using sinusoidal amplitude modulations (SAM).
Principal cells of the medial nucleus of the trapezoid body (MNTB) are simple round neurons that receive a large excitatory synapse (the calyx of Held) and many small inhibitory synapses on the soma.
These inhibitory inputs derive from the nuclei of the trapezoid body, which have physiological and structural specializations for high-fidelity temporal transmission, raising the possibility that well timed inhibition is involved in tuning ITD sensitivity.
NPR-C immunoreactivity was detected in several regions, including the periaqueductal gray, oculomotor nucleus, red nucleus and trochlear nucleus of the midbrain; the pontine nucleus, dorsal tegmental nucleus, vestibular nucleus, locus coeruleus, trigeminal motor nucleus, nucleus of the trapezoid body, abducens nucleus and facial nucleus of the pons; and the dorsal motor nucleus of the vagus, hypoglossal nucleus, lateral reticular nucleus, nucleus ambiguus and inferior olivary nucleus of the medulla oblongata.
Results from the study of twelve human brainstems provide evidence for six morphologically distinct cell groups: three within the trapezoid body and three along the posterior aspect of the SOC.
The medial nucleus of the trapezoid body (MNTB) is a distinct nucleus in the superior olivary complex that transforms excitatory input from the cochlear nucleus into a widespread inhibitory output to distinct auditory brainstem nuclei.
The medial nucleus of the trapezoid body (MNTB) is specialized for high frequency firing by expression of Kv3 channels, which minimize action potential (AP) duration, and Kv1 channels, which suppress multiple AP firing, during each calyceal giant EPSC.
Principal cells of the medial nucleus of the trapezoid body (MNTB) receive their excitatory input through large somatic terminals, the calyces of Held, which arise from axons of globular bushy cells located in the contralateral ventral cochlear nucleus.
They contact the principal cells of the medial nucleus of the trapezoid body (MNTB) with the very large calyx of Held that is one of the most secure synapses in the brain.
During development, GABA/glycinergic connections from the medial nucleus of the trapezoid body (MNTB) to the lateral superior olive (LSO) gradually change from being depolarizing to being hyperpolarizing.
Principal neurones of the mouse medial nucleus of the trapezoid body (MNTB) possess multiple voltage-gated potassium currents, including a transient outward current (or A-current), which is characterized here.
UBCs and granules are also present in regions previously not included in the GCS, namely the rostrodorsal magnocellular portions of ventral cochlear nucleus, vestibular nerve root, trapezoid body, spinal tract and sensory and principal nuclei of the trigeminal nerve, and cerebellar peduncles.
The total number of medial olivocochlear (MOC) neurons in the ventral nucleus of the trapezoid body (VNTB) is about 170 per side. DPO neurons, however, had more symmetric dendrites that projected into more dorsal parts of the trapezoid body, suggesting that this small group of olivocochlear neurons has very different physiological properties.
Among auditory nuclei, the majority of ChAT-IR cells are in the superior olive, particularly in and around the lateral superior olive, the ventral nucleus of the trapezoid body and the superior paraolivary nucleus.
METHODS: We performed a detailed pathoanatomical investigation of unconventionally thick tissue sections through the auditory brainstem nuclei (that is, nucleus of the inferior colliculus, nuclei of the lateral lemniscus, superior olive, cochlear nuclei) and auditory brainstem fibre tracts (that is, lateral lemniscus, trapezoid body, dorsal acoustic stria, cochlear portion of the vestibulocochlear nerve) of clinically diagnosed and genetically confirmed SCA2, SCA3 and SCA7 patients. Serial brainstem tissue sections stained for myelin showed loss of myelinated fibres in two of the auditory brainstem fibre tracts (that is, lateral lemniscus, trapezoid body) in a subset of patients.
Medial nucleus of the trapezoid body (MNTB) neurons, which inhibit the SPON, produce a sustained pure tone response followed by an offset response characterized by a period of suppressed spontaneous activity. This MNTB offset response is duration dependent and critical to the formation of SPON offset spikes [ Kadner A, Kulesza RJ Jr, Berrebi AS (2006) Neurons in the medial nucleus of the trapezoid body and superior paraolivary nucleus of the rat may play a role in sound duration coding.
Either FluoroGold or biotinylated dextran amine (BDA) injections in CRNs showed retrogradely labeled neurons in the ventral nucleus of the trapezoid body (VNTB).
In both normal and deaf mice, the ipsilateral projections from the anteroventral cochlear nucleus (AVCN) to the lateral superior olive (LSO), and the contralateral projections from the AVCN to the medial nucleus of the trapezoid body (MNTB) were intact.
In the adult hindbrain, the cytoplasmic Math5-lacZ reporter is expressed within the ventral cochlear nucleus (VCN), in a subpopulation of neurons that project to medial nucleus of the trapezoid body (MNTB), lateral superior olive (LSO), and lateral lemniscus (LL).
We evaluated two nuclei, the dorsal cochlear nucleus (DCN) and the medial nucleus of the trapezoid body (MNTB), which project in two distinct auditory pathways.
However, 6h after CHL manipulation, protein synthesis is up-regulated in MSO (bilaterally) and in the ipsilateral medial nucleus of the trapezoid body..
Ventral cochlear nucleus (VCN) axons normally project to the medial nucleus of the trapezoid body (MNTB) only on the contralateral side.
Both contribute to the low-voltage-activated potassium current I Kv1, which powerfully limits excitability and facilitates temporally precise transmission of information, e.g., in auditory neurons of the medial nucleus of the trapezoid body (MNTB).
The lateral superior olivary nucleus (LSO) is an auditory relay centre within the brain stem that encodes interaural level differences for sound localization by integrating GABA/glycinergic input from the contralateral ear via the medial nucleus of the trapezoid body (MNTB), and glutamatergic input from the ipsilateral ear via the ventral cochlear nucleus (VCN).
Neurons of the MOC system are located in the superior olivary complex, particularly in the dorsomedial periolivary nucleus (DMPO) and in the ventral nucleus of the trapezoid body (VNTB).
The calyx of Held synapse in the medial nucleus of the trapezoid body (MNTB) has been characterized in vitro as a fast relay that reliably fires at high stimulus frequencies (< or =800 Hz).
CO activity increased in the granular cell layer of dorsal cochlear nucleus, trapezoid body nucleus, intermediate lateral lemniscus, central and external inferior colliculus, and pyramidal cell layer of primary auditory cortex.
Syt 1 and syt 2 are localized predominantly to different subsets of synapses in retina, hippocampus, cerebellum, and median nucleus of the trapezoid body (MNTB).
At those times, labeling was also detected bilaterally in the medial nucleus of the trapezoid body and periolivary cell groups in the superior olivary complex.
Kv3.1b channel protein is widely distributed in the mammalian auditory brainstem, but studies have focused mainly on regions critical for temporal processing, including the medial nucleus of the trapezoid body (MNTB) and anteroventral cochlear nucleus (AVCN). Interestingly, cellular optical density declines were found in superior paraolivary nucleus, ventral nucleus of the trapezoid body, and lateral nucleus of the trapezoid body (24, 29, and 26%), which comprise the medial olivocochlear (MOC) feedback system.
The distribution of perineuronal nets and the potassium channel subunit Kv3.1b was studied in the subdivisions of the cochlear nucleus, the medial nucleus of the trapezoid body, the medial and lateral superior olivary nuclei, the lateral lemniscal nucleus and the inferior colliculus of the rhesus monkey. In the cochlear nucleus intensely and faintly stained perineuronal nets were intermingled, whereas in the medial nucleus of the trapezoid body the pattern changed to intensely stained perineuronal nets in the medial part and weakly labelled nets in its lateral part. The medial part of the medial nucleus of the trapezoid body showed a high number of GABAA binding sites whereas the lateral part exhibited more binding sites for GABAB.
In this study we examined the expression of neurotrophins in the mouse medial nucleus of the trapezoid body (MNTB) and investigated the effect of exogenous brain-derived neurotrophic factor (BDNF) application on the firing properties of MNTB principal cells.
The Slack (sequence like a calcium-activated K channel) and Slick (sequence like an intermediate conductance K channel) genes, which encode sodium-activated K+ (K(Na)) channels, are expressed at high levels in neurons of the medial nucleus of the trapezoid body (MNTB) in the auditory brainstem.
Such movements are abolished after pyramidotomy at the level of the trapezoid body.
Whole-cell patch-clamp recordings from principal neurons in the medial nucleus of the trapezoid body showed that a rise from 25 degrees C to 35 degrees C increased miniature EPSC (mEPSC) amplitude from -33 +/- 2.3 to -46 +/- 5.7 pA (n=6) and accelerated mEPSC kinetics.
SPON neurons use gamma-aminobutyric acid (GABA) as their neurotransmitter and are contacted by large numbers of glycinergic and GABAergic punctate profiles, representing a dense inhibitory innervation from the medial nucleus of the trapezoid body (MNTB) and from collaterals of SPON axons, respectively.
Labeled neurons were identified in the ventral nucleus of the trapezoid body and documented with the light microscope before being studied with serial-section electron microscopy.
The CaM III mRNAs were more than 2.5 times more abundant than the CaM II mRNAs in the nucleus of the trapezoid body, and more than two times more abundant in the motor trigeminal nucleus, the principal sensory trigeminal nucleus and the olivary nucleus.
The present review summarizes and discusses the morphology of five central excitatory synapses that are quantitatively well described: (1) a giant synapse, the so-called Calyx of Held, in the medial nucleus of the trapezoid body in the auditory brain stem, (2) the mossy fiber terminal establishing synapses with multiple cerebellar granule cell dendrites, (3) the mossy fiber bouton in the hippocampus predominantly terminating on proximal dendrites of CA3 pyramidal neurons, (4) the climbing fiber-Purkinje cell synapse in the cerebellum, and (5) cortical input synapses on the basal dendrites of layer 5 pyramidal cells.
Here we use a mouse model of congenital deafness (dn/dn- asymptomatic deafness associated with hair cell degeneration) to investigate the effect of lack of activity in the expression of Na(+) currents in neurons from the medial nucleus of the trapezoid body (MNTB).
We used electrophysiology and immunohistochemistry to investigate the properties of I(h) in three auditory brainstem nuclei in mice: the anteroventral cochlear nucleus (AVCN), the medial nucleus of the trapezoid body (MNTB) and the lateral superior olive (LSO).
c1502/QP-C mRNA was localized at high levels in the olfactory bulb, cerebral cortex, hippocampus, thalamus (anterodorsal nucleus, parafacicularis nucleus), tegmentum (red nucleus), cerebellum (Purkinje and granule cells), and pons (pontine nucleus, reticulotegmental nucleus, trapezoid body, vestibular nucleus).
By using brain slice preparations, direct patch-clamp recordings can be made from the nerve terminal and its postsynaptic target (principal neurons of the medial nucleus of the trapezoid body).
Histology was performed to assess the degree of sectioning of descending fiber tract connections to the cochlear nucleus, via the acoustic striae route, subpeduncular route, trapezoid body route, and ventral route of the olivocochlear bundle connection.
We examined how these channels participate in firing in the medial nucleus of the trapezoid body.
Brain stem auditory evoked potentials indicated a lack of crossing in the level of the trapezoid body.
In the auditory brainstem, the ventral cochlear nucleus (VCN) projects to the contralateral but not ipsilateral medial nucleus of the trapezoid body (MNTB).
In the medial nucleus of the trapezoid body (MNTB), channels containing the Kv1.1 subunit (encoded by the Kcna1 gene) underlie Ikl.
In fast-spiking neurons such as those in the medial nucleus of the trapezoid body (MNTB) in the auditory brainstem, Kv3.1 potassium channels are required for high frequency firing. We also measured the time course of dephosphorylation and recovery of basal phosphorylation of Kv3.1b following brief high frequency electrical stimulation of the trapezoid body, and we determined that the recovery process is mediated by both novel PKC-delta and PKC-epsilon isozymes and by conventional PKCs.
Cells in the anteroventral cochlear nucleus (aVCN) send out calyceal axons that form large excitatory somatic terminals, the calyces of Held, onto principal cells of the contralateral medial nucleus of the trapezoid body (MNTB).
After UCA, Western blotting was employed to quantify CREB-P levels and illustrate CREB levels in the anteroventral (AVCN), posteroventral (PVCN), and dorsal (DCN) cochlear nucleus; the lateral (LSO) and medial superior olive (MSO); the medial nucleus of the trapezoid body (MNTB); and the central nucleus of the inferior colliculus (ICc) for up to 145 days.
The pattern of expression of ionotropic glutamate receptor (GluR) subunits 1-4 in the medial nucleus of the trapezoid body (MNTB) has been reported to change during development.
Adenosine-triphosphate (ATP) is coreleased with several neurotransmitters and acts at presynaptic sites to reduce transmitter release; such presynaptic P2X receptors occur at inhibitory and excitatory terminals in the medial nucleus of the trapezoid body (MNTB).
The brainstem had markedly stained fibers in the medial longitudinal fasciculus and localized neuronal cell body labeling in the red n, mesencephalic trigeminal n, lateral reticular n, raphe obscurus n, solitary n, compact ambiguus n, motor trigeminal n and n of trapezoid body.
Previous immunolabelling studies in the medial nucleus of the trapezoid body (MNTB) have suggested that there may be gradients of voltage-gated currents underlying this tonotopic arrangement.
The medial nucleus of trapezoid body could be clearly differentiated as a distinct region in the rhesus monkey superior olivary complex.
No D/H-shift was observed in the medial nucleus of the trapezoid body (MNTB) until P10.
Single units in the medial nucleus of the trapezoid body (MNTB) and superior paraolivary nucleus (SPON) of anesthetized rats were studied.
Five nuclei in the SOC, the lateral superior olive (LSO), superior paraolivary nucleus (SPoN), and the medial, lateral, and ventral nuclei of the trapezoid body (MNTB, LNTB, and VNTB) were examined 14 days following the deafening and compared to normal hearing age-matched controls.
An inhibitory input from the contralateral ear, via the medial nucleus of the trapezoid body (MNTB), and excitatory input from the ipsilateral ear enable level differences to be encoded.
We have investigated spontaneous glycinergic miniature synaptic currents (mIPSCs) in principal cells of the medial nucleus of the trapezoid body.
Auditory nerve fibers (ANFs) were labeled by injecting DiI into the cochlea, and the contralateral projection to the medial nucleus of the trapezoid body (MNTB) by injecting DiI and GFP into the ventral cochlear nucleus.
Finally, the electrophysiological features of principal neurons of the medial nucleus of the trapezoid body did not change after P14, indicating that posthearing regulation of intrinsic membrane properties is not a general feature of all time-coding auditory neurons.
Interaural time and level difference processing by neurons in the superior olivary complex depends on synaptic inhibition from the medial nucleus of the trapezoid body (MNTB), a group of inhibitory neurons that is activated by contralateral sound stimuli.
The mammalian auditory pathways that compute the direction of a sound source are located in the brainstem and include the connection from bushy cells in the anteroventral cochlear nucleus (AVCN) to the principal neurons of the medial nucleus of the trapezoid body (MNTB).
In the medial nucleus of the trapezoid body (MNTB) the most medial neurons receive inputs corresponding to the highest frequency sounds and the most lateral neurons have the lowest characteristic frequencies.
Whole-cell recordings were made from visualized neurons in slices of the medial nucleus of the trapezoid body (MNTB) and anteroventral cochlear nucleus (AVCN).
Within the medial nucleus of the trapezoid body (MNTB) in the auditory brain stem, there is a large central synapse known as the calyx of Held, which mediates high-fidelity glutamatergic transmission.
In the central auditory pathways, FGF-2 immunoreactivity was found in the cytoplasm of the neurons of the cochlear nuclei, trapezoid body nuclei, medial geniculate nucleus, and inferior colliculus. Computer-assisted microdensitometric image analysis revealed higher levels of specific mean gray values of FGF-2 immunoreactivity in the trapezoid body and ventral cochlear nucleus and also in the spiral ganglion and inner hair cells.
Using microdissection and quantitative microassay, choline acetyltransferase (ChAT) activity was mapped in the cochlear nucleus (CN) and in the source nuclei of the olivocochlear bundle, the lateral superior olive and ventral nucleus of the trapezoid body. No gradient was found in the ventral nucleus of the trapezoid body. Decreases of ChAT activity were also found ipsilaterally in the lateral superior olive and bilaterally in the ventral nucleus of the trapezoid body.
The ventral nucleus of the trapezoid body (VNTB) strongly labels only for VGLUT2, despite the fact that glutamatergic synapses are present that are formed from collaterals of axons that go on to form synapses containing both VGLUT1 and VGLUT2. Principal neurons of the medial nucleus of the trapezoid body (MNTB) are surrounded by the calyx of Held presynaptic terminal, which is large enough to allow examination of VGLUT localization within a synapse.
5-HTT immunoreactivity (5-HTT-IR) was first observed in P8 mice and was localized to cell bodies in the ventral cochlear nucleus (VCN) and principal nuclei of the superior olivary complex, including the medial nucleus of the trapezoid body.
In vitro whole-cell patch recordings were made from medial nucleus of the trapezoid body (MNTB) neurones during 1 s excitatory postsynaptic current (EPSC) trains delivered at 200 Hz and at 37 degrees C.
In the lateral superior olive (LSO), a nucleus in the mammalian sound localization system that receives inhibitory input from the medial nucleus of the trapezoid body (MNTB), specific elimination and strengthening of synapses that are both GABAergic and glycinergic (GABA/glycinergic synapses) is essential for the formation of a precise tonotopic map.
Specifically, strong hybridization signals and immunoreactivity were found in the brainstem, including auditory neurons such as the medial nucleus of the trapezoid body.
In the adult SOC, VGLUT1 labeling varied from strong in the medial nucleus of the trapezoid body, lateral superior olive, and medial superior olive (MSO) to moderate (ventral and lateral nuclei of the trapezoid body) to faint (superior paraolivary nucleus).
Compared with auditory nerve (AN) fibers, trapezoid body (TB) fibers of the cat show enhanced synchronization to low-frequency tones.
Other labeled structures included the superior lateral parabrachial nucleus, the facial, hypoglossal and trigeminal motor nuclei, the nucleus incertus, the dorsal tegmental nucleus, the dorsal raphe nucleus, the nucleus of the trapezoid body, and the superficial layers of the dorsal horn of the spinal cord.
Contralateral inhibition of the nuclei of the trapezoid body (TB) was observed.
High levels of netrin-4 mRNA was found in the pyramidal cell layer of the cerebral cortex, prepiriform cortex, amygdaloid nuclei, pyramidal layer of hippocampus, Purkinje's cells, medial cerebellar nucleus and interposed cerebellar nucleus, medial nucleus of the trapezoid body and mitral cell layer of the olfactory bulb.
We have explored this issue in the rat medial nucleus of the trapezoid body (MNTB).
Here, we investigated the developmental expression pattern of calretinin and parvalbumin at a large excitatory synapse, the calyx of Held in the medial nucleus of the trapezoid body (MNTB) of rats and mice.
Loss of neurons was found in two nuclei of the auditory pathway of aged ASA(-/-) mice (ventral cochlear nucleus and nucleus of trapezoid body).
In adult, CNTFRalpha labeling occurred in most neurons of the cochlear nucleus (CN), the lateral superior olive (LSO), the medial superior olive (MSO), and the medial nucleus of the trapezoid body (MNTB).
No HCN1 staining was observed in the dorsal cochlear nucleus and the medial nucleus of the trapezoid body (MNTB).
Whole cell patch recordings from principal neurones of the medial nucleus of the trapezoid body (MNTB) showed strikingly enhanced excitability in the deaf mice when compared to control CBA mice at 12-14 days postnatal.
We investigated the mechanisms by which activation of group I metabotropic glutamate receptors (mGluRs) and CB1 cannabinoid receptors (CB1Rs) leads to inhibition of synaptic currents at the calyx of Held synapse in the medial nucleus of the trapezoid body (MNTB) of the rat auditory brainstem.
Concluding that LOC neurons cannot be the source of GAP-43 in the VCN, we reinvestigated the pattern of GAP-43 in situ hybridization and found that, after cochleotomy, shell neurons in the regions surrounding the LSO and medial olivocochlear (MOC) neurons in the ventral nucleus of the trapezoid body up-regulated GAP-43 mRNA.
The calyx of Held is a giant nerve terminal that forms a synapse directly onto the principal cells of the medial nucleus of the trapezoid body (MNTB) in the mammalian auditory brain stem.
The role of P2 receptors in synaptic transmission to the rat medial nucleus of the trapezoid body (MNTB) was studied in an in vitro brain slice preparation.
Areas or neuron groups expressing exclusively GLYT2 mRNA or GAD67 mRNA were rather limited, such as the superior colliculus, nucleus of the trapezoid body, and Purkinje cells.
These findings correlated with involvement of the auditory pathway at the level of the trapezoid body, and posterior corpus callosum in particular, on his brain MRI.
By employing retrograde tracing techniques, dextran-labeled neurons were found predominantly in the ipsilateral LOC system including lateral superior olive (LSO), and the surrounding periolivary regions (dorsal periolivary nucleus [ DPO], dorsolateral periolivary nucleus [ DLPO], lateral nucleus of trapezoid body [ LNTB]).
Labeled boutons were most numerous in the ventral nucleus of the trapezoid body, with additional boutons in all other olivary nuclei.
Biotin was detected in cells of the spiral ganglion, somata and proximal dendrites of cells in the cochlear nuclei, superior olivary nuclei, medial nucleus of the trapezoid body, and nucleus of the lateral lemniscus.
The mammalian medial nucleus of the trapezoid body (MNTB) harbors one of the most powerful terminals in the CNS, the calyx of Held.
We have recently applied Lindau-Neher's capacitance measurement technique to study vesicle trafficking at the calyx-type synapse in the rat medial nucleus of the trapezoid body (MNTB) in slice conditions.
Kv3.1 is expressed in a tonotopic gradient within the medial nucleus of the trapezoid body (MNTB) of the auditory brainstem, where Kv3.1 levels are highest at the medial end, which corresponds to high auditory frequencies.
After 145 postablation days, H-89 reversed elevations of [ 14C]GABA release in the medial nucleus of the trapezoid body (MNTB).
Principal neurons of the lateral superior olive (LSO) detect interaural intensity differences by integration of excitatory projections from ipsilateral bushy cells and inhibitory inputs from the medial nucleus of the trapezoid body.
In this simple circuit, ipsilateral sound increases firing of LSO neurons, whereas contralateral sound inhibits the firing rate via activation of the medial nucleus of the trapezoid body (MNTB).
Principal neurons of the medial nucleus of the trapezoid body (MNTB) receive a synaptic input from a single giant calyx terminal that generates a fast-rising, large excitatory postsynaptic current (EPSC), each of which are supra-threshold for postsynaptic action potential generation.
Following lesions of the medial paralemniscal nucleus, TIP39-immunoreactive fibers disappeared from the medial geniculate body, the periaqueductal gray, the deep layers of the superior colliculus, the external cortex of the inferior colliculus, the cuneiform nucleus, the nuclei of the lateral lemniscus, the lateral parabrachial nucleus, the locus coeruleus, the subcoeruleus area, the medial nucleus of the trapezoid body, the periolivary nuclei, and the spinal cord, suggesting that these regions receive TIP39-containing fibers from the medial paralemniscal nucleus, and unilateral lesions demonstrated that the projections are ipsilateral.
The second largest group consisted of medial OC neurons in the ventral nucleus of the trapezoid body, 75% of which were located contralaterally.
Glycinergic miniature inhibitory postsynaptic currents (mIPSCs) were recorded using patch-clamp methods in neurons from a brain slice preparation of the medial nucleus of the trapezoid body (MNTB), at 12-14 days postnatal age.
The voltage-gated potassium (Kv) channel subunit Kv1.1, encoded by the Kcna1 gene, is expressed strongly in the ventral cochlear nucleus (VCN) and the medial nucleus of the trapezoid body (MNTB) of the auditory pathway.
The analysis showed that FG-containing neurons as well as nNOS-immunoreactive neurons were present in the lateral superior olive (LSO), superior paraolivary nucleus (SPO), ventral nucleus of the trapezoid body (VNTB), medial superior olive (MSO) and in dorsal and ventral periolivary regions to different amounts.
Both H-89 and KN-93 elevated release in the medial nucleus of the trapezoid body (MNTB) and the contralateral MSO, suggesting that either kinase could be used by endogenous mechanisms in these nuclei to downregulate glutamatergic release..
The chopper cells had smaller, asymmetric, dendritic trees, which were either planar or marginal, had smaller somata and an output axon that left via the trapezoid body.
METHODS: Using the whole-cell voltage-clamp technique, we have studied changes in the electrophysiological properties of Na+ channels in the principal neurons of the medial nucleus of the trapezoid body (MNTB).
In the DCN and the medial nucleus of the trapezoid body (MNTB), the stimulatory effects of PDBu persisted after UCA.
These included octopus cells and spherical bushy cells of the cochlear nucleus and principal neurons of the medial nucleus of the trapezoid body.
Recordings were obtained from lateral superior olivary (LSO) neurons, and hyperpolarizing inhibitory potentials were evoked by stimulation of the medial nucleus of the trapezoid body (MNTB).
Third, labeled terminal arborizations in the LSO arose from collaterals of axons in the trapezoid body (output tract of planar cells).
A pre-embedding immunocytochemical method was used to study the subcellular distribution of the voltage-dependent potassium channel Kv3.1b in the medial nucleus of the trapezoid body (MNTB) in developing and adult rat.
It is formed in the superior olivary complex (SOC) by neurons of the medial nucleus of the trapezoid body, whose axons terminate in the lateral superior olive (LSO).
This efferent innervation is formed by two separate systems: the lateral system, which originates in the lateral superior olive (LSO) and reaches the inner hair cells; and the medial system, which originates in the ventral nucleus of the trapezoid body (VNTB) and innervates the OHCs.
In rats, this nucleus is composed of a morphologically homogeneous population of GABAergic neurons that receive excitatory input from the contralateral cochlear nucleus and inhibitory input from the ipsilateral medial nucleus of the trapezoid body.
Kv1.1 is strongly expressed in neurons with IKL, including auditory neurons of the medial nucleus of the trapezoid body (MNTB).
Neurons of the medial nucleus of the trapezoid body, which transmit auditory information that is used to compute the location of sounds in space, are capable of firing at high frequencies with great temporal precision. A partial decrease in Kv3.1 current can be produced in wild-type neurons of the medial nucleus of the trapezoid body by activation of protein kinase C.
We examined the development of functional connectivity before hearing onset in rats in the tonotopically organized, glycinergic pathway from the medial nucleus of the trapezoid body (MNTB) to the lateral superior olive (LSO), which is part of the mammalian sound localization system.
We have studied glycinergic mIPSCs in two auditory brainstem nuclei, the rat anteroventral cochlear nucleus (AVCN) and the mouse medial nucleus of the trapezoid body (MNTB).
A coherent nuclear structure that could be addressed as the medial nucleus of the trapezoid body was not identified by any single one or by combinations of the markers used.
Immunocytochemical procedures revealed OT-immunoreactive perikarya and/or fiber terminals in restricted areas of the inferior colliculus (IC), superior olivary complex (SOC), including the medial and ventral nuclei of the trapezoid body, and in the cochlear nucleus.
The three-dimensional morphology of the axosomatic synaptic structures between a calyx of Held and a principal neuron in the medial nucleus of the trapezoid body (MNTB) in the brainstem of young postnatal day 9 rats was reconstructed from serial ultrathin sections.
Activation of ionotropic glycine receptors potentiates glutamate release in mature calyceal nerve terminals of the rat medial nucleus of the trapezoid body, an auditory brainstem nucleus.
In the auditory system, inhibitory transmission from the medial nucleus of the trapezoid body (MNTB) to neurons of the lateral superior olivary nucleus (LSO) undergoes activity-dependent long-term depression, and may be associated with developmental elimination of these synapses [ Sanes DH, Friauf E (2000).
We have used this method for exploring transmission in the auditory brainstem at the medial nucleus of the trapezoid body neurones, which are innervated by axons from the contralateral cochlear nucleus. Since <10% of the medial nucleus of the trapezoid body neurones retain viable synaptic inputs following the slicing procedure, preselecting those cells with active synapses dramatically increased our recording success.
At embryonic day 12, neurons in the ventral nucleus of the trapezoid body were first to express ChAT.
In the medial nucleus of the trapezoid body (MNTB), I(LT) ensures generation of single APs during each EPSP, so that the timing and pattern of AP firing is preserved on transmission across this relay synapse (calyx of Held).
The immunoreactivity of the neurokinin receptors was found to be widely distributed in most neurons of the cochlear nucleus (CN), the lateral superior olive (LSO), the medial nucleus of the trapezoid body (MNTB) and in the inferior colliculus (IC).
The medial nucleus of the trapezoid body (MNTB) plays an important role in the processing of interaural intensity differences, a feature that is critical for the localization of sound sources.
Second, inputs from octopus and multipolar/stellate cells of the cochlear nucleus and from principal cells of the medial nucleus of the trapezoid body could relate to precise temporal processing in the SPN.
The medial nucleus of the trapezoid body (MNTB) acts as a relay nucleus in the transmission of auditory information from the cochlear nucleus (CN) to the lateral superior olive.
These neurons resided in the posteroventral and anteroventral cochlear nucleus, the dorsal cochlear nucleus, the lateral superior olive, the medial nucleus of the trapezoid body, the dorsal and ventral nucleus of the lateral lemniscus, and the central nucleus of the inferior colliculus.
Using whole-cell recordings from presynaptic terminals and postsynaptic principal neurons in the mouse medial nucleus of the trapezoid body (MNTB), we have characterized properties of the calyx of Held synapse during the first three postnatal weeks.
The lateral superior olive (LSO), a binaural nucleus involved in sound localization, receives tonotopically organized inhibitory inputs from the medial nucleus of the trapezoid body (MNTB).
Here we investigate, during postnatal development, the effect of noradrenaline (NA) at the calyx of Held synapse in the rat medial nucleus of the trapezoid body (MNTB).
The results of a quantitative light microscopic analysis of serial glycine immunoreacted sections through the medial nucleus of the trapezoid body (MNTB) of young and old gerbils are presented.
The synchronization of transmitter release in the synapse of the medial nucleus of the trapezoid body (MNTB) is achieved during early postnatal development as a consequence of elimination of delayed asynchronous releases and appears to reflect changes in the dynamics of Ca(2+) entry and clearance.
The lateral superior olive (LSO), a nucleus involved in sound localization, receives tonotopically organized, inhibitory input from the medial nucleus of the trapezoid body (MNTB).
To address this question, we have applied immunocytochemical and electrophysiological techniques to the calyx of Held synapse in the medial nucleus of the trapezoid body (MNTB) of rat auditory brainstem.
Glycine release from the medial nucleus of the trapezoid body (MNTB) synapse was mediated predominantly by P/Q-type Ca(2+) channels, but with a significant contribution from N-type Ca(2+) channels.
Cholinergic currents, driven by neurons in the ventral nucleus of the trapezoid body that are likely to include medial olivocochlear efferents, excite T stellate cells, but have subtle effects on the firing of bushy cells, and have no detectable influence on octopus cells and D stellate cells.
These have been located at the brainstem in neurons belonging to the lateral superior olive (lateral efferent system) or in neurons of the periolivary region around the medial superior olive and the trapezoid body (medial efferent system).
Paired whole-cell recordings were made from a glutamatergic giant nerve terminal, the calyx of Held, and its postsynaptic target cell in the medial nucleus of the trapezoid body (MNTB) in the brainstem slice of juvenile rat.
However, neurons in the medial nucleus of the trapezoid body remained immunopositive for both BDNF and NT-3. Fibers in the trapezoid body were labelled with BDNF immunoreactivity by P12.
The main source of excitation to the ventral cochlear nucleus (VCN) is from glutamatergic auditory nerve afferents, but the VCN is also innervated by two groups of cholinergic efferents from the ventral nucleus of the trapezoid body.
The vast majority of glycinergic inputs to SPON are presumed to originate in the ipsilateral medial nucleus of the trapezoid body, but the source(s) of its GABAergic innervation remains to be determined..
This investigation examines temporal processing through successive sites in the rat auditory pathway: auditory nerve (AN), anteroventral cochlear nucleus (AVCN) and the medial nucleus of the trapezoid body (MNTB).
Data were collected from units in successive processing sites of auditory pathway: the auditory nerve, the cochlear nucleus, the trapezoid body and the medial nucleus of the trapezoid body.
The intensity of Kv3.1 immunoreactivity varied across the tonotopic map in the medial nucleus of the trapezoid body with neurons responding best to high-frequency tones most intensely labeled.
We have previously described the anatomical refinement of an inhibitory projection from the medial nucleus of the trapezoid body to the lateral superior olive in the developing gerbil auditory brain stem. When whole cell recordings were made from lateral superior olive neurons in a brain slice preparation, the long-lasting depression of medial nucleus of the trapezoid body-evoked inhibitory potentials was eliminated by the GABA(B) receptor antagonist, SCH-50911.
Postnatal development of Ca2+ influx and Ca2+ clearance capacity were investigated in the synapse of medial nucleus of the trapezoid body (MNTB) of rat with fura-2 fluorimetry.
Excitatory postsynaptic currents (EPSCs) were recorded using the whole-cell patch-clamp technique at the calyx of Held synapse in the medial nucleus of the trapezoid body (MNTB) in auditory brainstem slices from juvenile rats.
Here we report evidence for presynaptic ionotropic glycine receptors, using pre- and postsynaptic recordings of a calyceal synapse in the medial nucleus of the trapezoid body (MNTB).
The medial nucleus of the trapezoid body of the auditory system is involved in the localization of sounds in the space. To investigate whether group II mGluRs are present in the medial nucleus of the trapezoid body, we have studied the pattern of expression of mGluR2/3 in the developing and mature nucleus by means of immunocytochemichal methods. Activation of these receptors might be relevant to the maturation and modulation of synaptic transmission in the medial nucleus of the trapezoid body..
To find out whether glycine and aspartate may occur in net-bearing neurons the present study was focused on the rat medial nucleus of the trapezoid body (MNTB) which contains a large portion of cells immunoreactive for these amino acids, but appears to be devoid of GABA-immunoreactive cell bodies.
In the present study, it was indicated by a highly sensitive immunocytochemical method with a D-serine specific antibody that D-serine was contained not only in astrocytes but also in some neurons, such as pyramidal neurons in the cerebral cortex, and neurons in the nucleus of the trapezoid body.
These findings were also confirmed in native Kv3.1 channels expressed in medial nucleus of the trapezoid body (MNTB) neurons.
Mechanisms contributing to the synchronisation of transmitter release during development were studied in synapses of the medial nucleus of the trapezoid body (MNTB) using patch recording and Ca2+ imaging techniques in a rat brainstem slice preparation.
The medial superior olive (MSO) is part of the binaural auditory pathway, receiving excitatory projections from both cochlear nuclei and an inhibitory input from the ipsilateral medial nucleus of the trapezoid body (MNTB).
The much smaller human lateral olivary nucleus probably functions in analysis of interaural differences in frequency and intensity, but the absence of a human nucleus of the trapezoid body implies some difference in the mechanisms of this function.
The main nuclei of the ascending system, the lateral and medial superior olive (LSO, MSO), as well as the lateral and medial nuclei of the trapezoid body (LNTB, MNTB), have been traditionally associated with sound localization.
New data are provided that show a differential distribution of serotoninergic afferents within the SOC: serotoninergic fibers were relatively sparse in the lateral and medial superior olives and the medial nucleus of the trapezoid body and were most numerous in periolivary regions. These include: cochlear nucleus afferents to periolivary (lateral nucleus of the trapezoid body, LNTB) cells that project to the inferior colliculus; cortical afferents to periolivary (ventral nucleus of the trapezoid body, VNTB) cells that project to the cochlear nucleus; and serotoninergic and noradrenergic afferents to periolivary (LNTB and VNTB) cells that project to the cochlear nucleus.
Their largest numbers and percentages of total cells were observed in the medial nucleus of the trapezoid body.
Neuropathological examination revealed glial fibrillary tangles (GFTs) mainly distributed in the putamen, caudate nucleus, thalamic nuclei, substantia nigra, red nucleus, globus pallidus, trapezoid body, pyramid, pons and medulla oblongata of the brain, and neurofibrillary tangles (NFTs) in the thalamic nuclei.
HCN1 expression is highly enriched in cerebral cortex, hippocampus, cerebellum, and facial motor nucleus; HCN2 is highly abundant in mamillary bodies, pontine nucleus, ventral cochlear nucleus, and nucleus of the trapezoid body; HCN3 expression is most pronounced in supraoptic nucleus of hypothalamus; and HCN4 expression is most abundant in medial habenula and anterior and principal relay nuclei of the thalamus.
Some of the neurons located ventrally within the nucleus possess dendrites that extend ventrally beyond the limits of the SPON to penetrate into the underlying ventral nucleus of the trapezoid body.
The topographic inhibitory projection from the medial nucleus of the trapezoid body (MNTB) to the lateral superior olive (LSO) undergoes synapse elimination during development (Sanes and Takács, 1993).
By contrast, a majority, and possibly all, olivocochlear neurons residing in the ventral nucleus of the trapezoid body (VNTB), the medial olivocochlear cells (MOCs), do have such axon collaterals.
Expression was assessed in three SOC nuclei, the lateral and medial superior olives (LSO, MSO) and the medial nucleus of the trapezoid body (MNTB).
Using combined retrograde and anterograde tracing we describe close contacts between medial olivocochlear neurones and corticofugal terminals in the ventral nucleus of the trapezoid body.
In the rat, the outer hair cells in the cochlea receive direct synaptic input from neurones in the ventral nucleus of the trapezoid body.
In the rat, the former is constituted by neurons located in the lateral superior olivary nucleus, that project to the inner hair cells, while the later originates in the ventral nuclei of the trapezoid body and project to the outer hair cells.
Immunoreactive fibres were observed in the following; the inferior central nucleus; the pontine gray nuclei; the Kölliker-Fuse nucleus; the motor trigeminal nucleus, the anteroventral cochlear nucleus; the abducens nucleus; the retrofacial nucleus; the superior, lateral, inferior, and medial vestibular nuclei; the lateral nucleus of the superior olive; the external cuneate nucleus; the nucleus of the trapezoid body; the postpyramidal nucleus of the raphe; the medial accessory inferior olive; the dorsal accessory nucleus of the inferior olive; the nucleus ambiguus; the principal nucleus of the inferior olive; the preolivary nucleus; the nucleus ruber; the substantia nigra; and in the area postrema.
The most distinct changes were observed in the medial nucleus of the trapezoid body.
We establish rank order for each channel's expression in each region, finding that the medial nucleus of the trapezoid body shows the highest signal for each of the four channel genes.
A new form of synaptic depression of excitatory synaptic transmission was observed when making voltage-clamp recordings from large presynaptic terminals, the calyces of Held and postsynaptic cells, the principal cells of the medial nucleus of the trapezoid body (MNTB), in slices of the rat auditory brainstem.
These transporters are found in the dorsal cochlear nucleus (DCN) and medial nucleus of the trapezoid body. Decreases in auditory primary afferent activity, caused by either unilateral labyrinthectomy or disruption of the middle ear ossicles, caused a reduction in Glyt2, but not Glyt1 mRNA in the ipsilateral DCN and in the contralateral medial nucleus of the trapezoid body.
CRN axons, which are remarkably thick, enter the trapezoid body, cross the midline, and ascend in the rostral aspect of the lateral lemniscus to reach the upper levels of the midbrain.
In the brain stem, there were immunoreactive neurons and fibers in the tractus solitarius and nucleus, trigeminal spinal tract and nuclei, periaqueductal gray matter, vestibular nuclei, cochlear nuclei, trapezoid body, medial geniculate nucleus, and red nucleus.
The comparison with retrogradely labeled neurons showed that perikarya in the lateral superior olivary nucleus and, in particular, the medial nucleus of the trapezoid body were double-labeled.
To address the mechanism underlying PESP, we have made paired whole-cell recordings from the giant presynaptic terminal, the calyx of Held, and its postsynaptic target in the medial nucleus of the trapezoid body in rat brainstem slices.
Substantial brevican immunoreactivity was detected in a number of nuclei and in the reticular formations throughout the midbrain and hindbrain, including, but not limited to, the deep cerebellar nuclei, the trapezoid body, the red nucleus, the oculomotor nucleus, the vestibular nucleus, the cochlear nucleus, the gigantocellular reticular nucleus, the motor trigeminal nucleus, and the lateral superior olive.
A preembedding immunocytochemical method for light microscopy was used to study the postnatal development of expression of the group III metabotropic glutamate receptor mGluR4a in the medial nucleus of the trapezoid body (MNTB) of the rat.
In accordance with the literature, we observed neurons innervating the IC located in the lateral superior olivary nucleus (LSO) and dorsal periolivary groups (DPO) on both sides, in the superior paraolivary nucleus (SPO) predominantly ipsilateral, as well as in the ipsilateral medial superior olivary nucleus (MSO) and the medial nucleus of the trapezoid body (MNTB).
Double-labeled cells were present in almost all periolivary nuclei; the majority were located in the ventral nucleus of the trapezoid body and the anteroventral periolivary nucleus.
Immunostaining of planar neurons was light, comparable to that of excitatory neurons (pyramidal neurons in the DCN), whereas immunostaining of radiate neurons was dark, comparable to that of glycinergic neurons (cartwheel cells in the dorsal cochlear nucleus and principal cells in the medial nucleus of the trapezoid body).
We studied the relation between the size of presynaptic calcium influx and transmitter release by making simultaneous voltage clamp recordings from presynaptic terminals, the calyces of Held and postsynaptic cells, the principal cells of the medical nucleus of the trapezoid body, in slices of the rat brainstem.
N-Methyl-D-aspartate receptor-2A, -2B and -2C expression was detected over cells in the lateral and medial superior olive, the medial, lateral and ventral nucleus of the trapezoid body, and the superior paraolivary nucleus. N-Methyl-D-aspartate receptor-2D expression was only observed in the lateral superior olive, lateral nucleus of the trapezoid body and ventral nucleus of the trapezoid body. The lateral superior olive and ventral nucleus of the trapezoid body showed higher expression of N-methyl-D-aspartate receptor-2A and -2C than other subunits; the medial nucleus of the trapezoid body showed higher N-methyl-D-aspartate receptor-2B expression than other subunits; and the medial superior olive, superior paraolivary nucleus and ventral nucleus of the trapezoid body showed relatively equivalent expression of N-methyl-D-aspartate receptor-2A, -2B and -2C subunits. N-Methyl-D-aspartate receptor-2D had the lowest expression, with levels greater than background in only the lateral superior olive, ventral nucleus of the trapezoid body and lateral nucleus of the trapezoid body.
In the cochlear nucleus, neurons and nerve fibres were stained with the P2X2 antibodies, as were the neurons in the trapezoid body.
In neonatally undernourished and binaural ear-occluded animals, a significant reduction in the number of dendrites and dendritic intersections in the medial trapezoid body neurons was observed. Control and undernourished rats with binaural ear occlusion exhibited a significant increase in the dendritic arbor measurements of lateral superior olivary neurons as compared with the cells of the medial trapezoid body.
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