The medial nucleus of the trapezoid body: Comparative physiology

Kopp‐Scheinpflug, Conny; Tolnai, Sandra; Malmierca, Manuel S.; Rübsamen, Rudolf

doi:10.1016/j.neuroscience.2008.01.088

Cited by 114 publications

(115 citation statements)

References 77 publications

Supporting

Mentioning

106

Contrasting

Order By: Relevance

“…This is in line with in vivo studies in which brief tone stimulation (50 ms) evokes few spike failures (Lorteije et al, 2009;Lorteije and Borst, 2011). However, when challenged physiologically with high-frequency stimuli (Ͼ400 Hz) that are relatively long in duration, our results predict that more spike failures are likely to occur, which agrees with the in vivo findings of Kopp-Scheinpflug et al (2008) and Lorteije and Borst (2011). Thus, the principal MNTB cells likely to transmit reliably for long-duration stimuli are those innervated by morphologically complex calyces, which are more resistant to synaptic depression.…”

Section: Calyx Morphology and Form Of Stp Determine Spike Output Of Psupporting

confidence: 91%

“…To further mimic in vivo conditions in which spontaneous activity is usually present (Hermann et al, 2007), we recorded cell-attached I AP evoked by high-frequency test trains at 35°C after a conditioning train (4 s at 50 Hz). The conditioning frequency of 50 Hz was selected based on values in the in vivo study performed in mice by Lorteije et al (2009), which reported an average spontaneous frequency of ϳ70 Hz, and the studies by Kopp-Scheinpflug et al (2008) and Sonntag et al (2009), which reported an average spontaneous frequency of ϳ30 Hz. After the recordings performed at 35°C, the bath temperature was once again reduced to room temperature, and EPSCs during 100 -300 Hz trains were recorded.…”

Section: Methodsmentioning

confidence: 99%

“…In a subset of experiments, we mimicked in vivo-like conditions by recording at physiological temperature and incorporating spontaneous activity that is typically present in vivo (Hermann et al, 2007;Kopp-Scheinpflug et al, 2008;Lorteije et al, 2009;Sonntag et al, 2009). We found large variability in the incidence of postsynaptic failures except that the onset of the failure variability within the data occurred at higher stimulation frequencies compared with the standard conditions (i.e., room temperature) and that type III synapses again exhibited higher fidelity of firing than type I synapses.…”

Section: Stp and Postsynaptic Spike Failuresmentioning

confidence: 98%

“…We recorded I AP from principal MNTB neurons (n ϭ 10) during test trains of varying frequencies at 35°C and when the trains were preceded by a 4 s 50 Hz conditioning train to consider the roles of temperature and spontaneously active afferent axons normally present in vivo (Taschenberger and von Gersdorff, 2000;Futai et al, 2001;Kushmerick et al, 2006;Yang and Wang, 2006;Fedchyshyn and Wang, 2007;Hermann et al, 2007;Kopp-Scheinpflug et al, 2008;Lorteije et al, 2009;Sonntag et al, 2009). When bath temperature was raised to 35°C, spike failures occurred at higher stimulation frequencies compared with room temperature independent of the form of STP expressed at the synapse.…”

Section: Incidence Of Spike Failures Is Highly Variable In Principal mentioning

confidence: 99%

See 3 more Smart Citations

Morphological and Functional Continuum Underlying Heterogeneity in the Spiking Fidelity at the Calyx of Held SynapseIn Vitro

Grande¹,

Wang²

2011

J. Neurosci.

View full text Add to dashboard Cite

Reliable neuronal spiking is critical for a myriad of computations performed by neural circuits. This is particularly evident for sound localization cues in the auditory brainstem circuits that detect timing and intensity differences of sounds arriving at two ears. The calyx of Held-principal neuron synapse in the medial nucleus of the trapezoid body (MNTB) in this circuit is traditionally viewed as a reliable relay, which converts contralateral excitatory inputs to inhibitory outputs to ipsilateral superior olive neurons that code interaural timing and intensity differences. However, recent studies demonstrated large variability in the incidence of postsynaptic spike failures at this synapse, challenging the view that this synapse is a fail-safe relay. Using combined imaging and paired recordings in mature (P16 -P19) mouse brainstem slices, we show that spike failure rates of MNTB neurons are strongly correlated with differences in gross morphology of the calyx terminal and quantal properties under standard in vitro-and in vivo-like conditions. MNTB neurons innervated by calyces with simple morphologies (mainly digits) express strong short-term synaptic depression and a high incidence of spike failures after high-frequency stimulation. Conversely, MNTB neurons innervated by structurally complex calyces (digits and numerous bouton-like swellings) exhibit initial facilitation followed by slow depression and very few spike failures. Our results indicate that the calyx of Held-MNTB synapse is likely organized as a structural and functional continuum, in that correlated heterogeneities in calyx morphology and short-term plasticity serve as a filter for regulating the inhibition delivered to superior olive neurons during sound localization.

show abstract

Section: Calyx Morphology and Form Of Stp Determine Spike Output Of Psupporting

confidence: 91%

Section: Methodsmentioning

confidence: 99%

Section: Stp and Postsynaptic Spike Failuresmentioning

confidence: 98%

Section: Incidence Of Spike Failures Is Highly Variable In Principal mentioning

confidence: 99%

See 2 more Smart Citations

Morphological and Functional Continuum Underlying Heterogeneity in the Spiking Fidelity at the Calyx of Held SynapseIn Vitro

Grande¹,

Wang²

2011

J. Neurosci.

View full text Add to dashboard Cite

show abstract

“…9 for a review). Firing rates between 50 Hz and 300 Hz are quite 'physiological' in the auditory pathway 1 . As a consequence, the calyx of Held synapse is in a state of 'short-tem depression' during normal operation.…”

Section: Box 1 | Presynaptic Organization -Exocytic and Endocytic Zonesmentioning

confidence: 99%

Protein scaffolds in the coupling of synaptic exocytosis and endocytosis

2011

View full text Add to dashboard Cite

Communication between nerve cells largely occurs at chemical synapses -specialized sites of cell-cell contact where electrical signals trigger the exocytic release of neurotransmitter, which in turn activates postsynaptic receptor channels. The efficacy with which such chemical signals are transmitted is crucial for the functioning of the nervous system. Modulation of neurotransmission enables nerve cells to respond to a vast range of stimulus patterns. Synaptic activity can also be tremendously diverse; from the fast synapses of the hippocampus, to slow neuropeptide-containing synapses. Indeed, some signalling pathways are active in the absence of stimulation, such as those involved in the processing of sensory information, which transmit tonically at high rates of up to 100 Hz or more 1,2 .Intriguing questions arise from these facts, including how high rates of neurotransmission can be maintained over long periods of time, and what limits the ability of a given synapse to release neurotransmitter during sustained periods of activity. Recent data indicate that in many synapses, exocytosis of neurotransmitter is coupled to endocytosis, and that synapses have evolved a specialized apparatus of scaffolding proteins to comply with these demands. Such scaffolds aid the temporal and spatial coupling of exocytosis and endocytosis, and are crucial for maintaining rapid neurotransmission during sustained activity 3 .Exocytosis of neurotransmitter is triggered by stimulusinduced calcium influx into the nerve terminal 4,5 and the subsequent fusion of synaptic vesicles with the presynaptic plasma membrane at specialized regions called active zones (BOX 1). Exocytosed synaptic vesicle membrane proteins and lipids in turn are recycled at the endocytic or periactive zone (BOX 1) that surrounds the release site, to restore functional synaptic vesicle pools for reuse and to ensure long-term functionality of the synapse 6-8 (FIG. 1). Depending on the type of synapse and the stimulation frequency, several modes of endocytosis with different time constants -for example, fast and slow endocytosisseem to operate 7,9,10 . Clathrin-mediated endocytosis arguably represents the main pathway of synaptic vesicle endocytosis 6,8,11 , although other modes -for example, fast kiss-and-run exocytosis and endocytosis -could operate in parallel.Although the machineries for exocytic membrane fusion 12,13 and for endocytic retrieval of synaptic vesicle membranes have been studied separately in some detail 6,14 , comparatively little is known about the coupling between exocytosis and endocytosis. Here we synthesize recent data from physiological, morphological and biochemical studies in several model systems into hypothetical models for scaffold-based mechanisms underlying exocytic-endocytic coupling.The synaptic vesicle cycle Synaptic vesicle pools. Some defining features of chemical synapses are the presence of one or several clusters of synaptic vesicles in the presynaptic nerve terminal, and ultrastructural specializations at the pre-and postsy...

show abstract

Treatment outcome in young adults and children >10 years of age with acute lymphoblastic leukemia in Sweden

Hallböök

Gustafsson

Smedmyr

et al. 2006

Cancer

161

View full text Add to dashboard Cite

The optimal treatment of advanced sporadic Burkitt lymphoma in adults is still a matter of debate. The salutary results of pediatric therapies did open the road for improving the adult outcome. Between May 1988 and March 2009, 71 consecutive patients—46 adults, 25 children—affected by Burkitt lymphoma/leukemia were treated with the same intensive pediatric protocol alternating vincristine, adriamycine and fractionated ciclophosphamide (phase A) with high dose methotrexate and high dose cytarabine (phase B) in four Italian institutions. Eighty‐nine per cent of patients were in Stage III–IV or had L3 leukemia. Complete remissions were 67/71 (94.4%), 24/25 (96%) in children, and 43/46 (93.5%) in adults. Toxic deaths were 3/71 (4.2%), all in adults. There were nine relapses (one in children, eight in adults), all but one observed early. After a median observation of 94 months (range 23–275), the Event–Free Survival rate is 92% in children and 71.7% in adults (P = 0.067). The 23 more recent adults received also rituximab, without differences in outcome as compared to patients who did not. Our experience confirms that such an intensive pediatric‐derived chemotherapy is feasible and improves the long‐term outcome of adults with advanced Burkitt lymphoma. Am. J. Hematol., 2012. © 2011 Wiley Periodicals, Inc.

show abstract

The medial nucleus of the trapezoid body: Comparative physiology

Cited by 114 publications

References 77 publications

Morphological and Functional Continuum Underlying Heterogeneity in the Spiking Fidelity at the Calyx of Held SynapseIn Vitro

Morphological and Functional Continuum Underlying Heterogeneity in the Spiking Fidelity at the Calyx of Held SynapseIn Vitro

Protein scaffolds in the coupling of synaptic exocytosis and endocytosis

Treatment outcome in young adults and children >10 years of age with acute lymphoblastic leukemia in Sweden

Contact Info

Product

Resources

About