Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 17 of 17 for “"transmitter release"”.
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Modeling physiological calcium signaling for fast transmitter release at a central synapse : topography of release sites and its functional significance
… thesis addresses how calcium channels and neurotransmitter vesicles at release sites are spatially organized to control fast synaptic transmission in the central nervous system (topography of release sites). The problem, investigated here for the giant synapse calyx of Held, has been addressed …
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Real time course of transmitter release of SSVs and LDCVs; SNARE function analysed in synaptobrevin2 and cellubrevin knock out mice
Teil 1Die Freisetzung von Neurotransmittern wird durch die Ca2+-abhängige Exocytose von synaptischen Vesikeln vermittelt, die eine sehr schnelle Kinetik der Transmitterfreisetzung aufweist. Mit Hilfe von Kohlefasern als elektrochemische Detektoren wurde die Freisetzung des Neurotransmitters …
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Decreased transmitter release conferred by a mutation in the slowpoke-encoded calcium-dependent potassium channel gene at the Drosophila neuromuscular junction
… slo mutants show significant reductions in transmitter release. Also, slo mutations paired with hyperexcitable mutants (Shaker, ether a go go) and/or pharmacological agents (4-aminopyridine) significantly decrease the high amounts of transmitter release normally observed in these situations. …
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A possible role for intrinsic calcium buffers in the long- term adaptation of crayfish neurons
… vivo over 3 or more days causes a reduction in transmitter release that persists for days or weeks (eg. Mercier and Atwood, 1989). This effect is usually accompanied by decreased synaptic fatigue. These two changes involve presynaptic mechanisms and indicate "long-term adaptation" (LTA) of nerve …
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Mechanisms of Calcium Buffering and Aging in Neurons: Testing the Limits of Homeostasis
… gene expression, synaptic plasticity, transmitter release, excitability, and even cell death. Upon neuronal excitation the [Ca<sup>2+</sup>]i increases rapidly and the calcium buffering system reacts quickly to restore [Ca<sup>2+</sup>]i to basal levels in order to reset the cell for …
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Manipulation and characterization of proopiomelanocortin (POMC) neurons in the hypothalamic regulation of energy balance
… the maintenance of energy balance. POMC neurons release peptide transmitters that modulate pathways involved in food intake, energy expenditure, and reward pathways. POMC peptide release can result in the inhibition of food intake and increased activation of these cells is thought to precipitate …
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The role of auditory sensory input during functional pre- and postsynaptic maturation of the calyx of Held synapse
… presynaptic Ca2+ channel subtypes governing transmitter release at the cochlear inner hair cell (IHC)-spinal neuron synaptic junction compared to those at higher synapses along the auditory pathways. We characterized functional properties of calyx synapses in wildtype (wt) compared to those …
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Transfer Properties of the Hair Cell-Afferent Fiber Synapse
… measurements, and iontophoresis. Glutamate is released from hair cells in response to Ca<sup>2+</sup> influx through L-type Ca<sup>2+</sup> channels and is detected by AMPA receptors in postsynaptic fibers. Gradations in the extent of presynaptic stimulation are encoded by a linear increase in …
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On the transmission properties of synapses made between granule cells and cerebellar Purkinje cells
… analysis of EPSCs in rat PCs confirmed that the release sites of AA synapses have a greater probability of transmitter release than PF synapses. Furthermore, AA release sites have greater mean quantal amplitude than PF synapses, which is not due to a different type of postsynaptic receptor. AA …
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Modulation of hippocampal sharp wave-ripple activity in vitro
… by NE was linked to presynaptic modulation of transmitter release via α1 ARs-mediated reduction in presynaptic Ca2+ uptake. Nicotine, in moderate doses, facilitated expression and induction of SPW-Rs and transformed them into REDs at high concentration. This transition was associated with …
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Nucleus accumbens dopamine and investigatory behavior : modulation by the ventral subiculum of the hippocampus through the dopamine cell bodies of the ventral tegmental area
… at least in part, by evoking glutamate-mediated transmitter release from NAS dopaminergic terminals. As the VS is not known to project to the VTA, the possibility that the VS influences dopaminergic transmission at the cell body level has largely been overlooked. In the present thesis, in vivo …
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Genetic Mutations of K<sub>Ca</sub>2.3 and K<sub>Ca</sub>3.1 Channels Affect Ca2+ Sensitivity
… properties of neurons to the control of the transmitter release. The Ca<sup>2+</sup> sensitivity of these channels allows intracellular Ca<sup>2+</sup> to regulate the electrical activity of the cell membrane. Increased Ca<sup>2+</sup> sensitivity of K<sub>Ca </sub>channels caused by gain of …
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Regulation of Synaptic Vesicle Trafficking at Central Synapses
… approaches, I propose that La³⁺ induces transmitter release via narrow fusion pore opening and closure, or a ‘kiss-and-run’ mode of exo- and endocytosis. Chapter four investigates the molecular requirement for the synaptic vesicle recycling pathway. I analyzed the impact of one of main …
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Zur Funktion der Kinase Dyrk1A im Gehirn der adulten Maus
… vesicles with the presynaptic membrane and transmitter release. The results of this study contribute to the understanding of the role of Dyrk1A in physiological and pathophysiological contexts. Eventually, this should help (i) to elucidate the mechanisms that lead to mental retardation in …
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Vitamin E : elucidation of the mechanism of side chain degradation and gene regulatory functions
… is a marked difference in the amount of the release of metabolites from the individual vitamin E forms in cell culture as well as in experimental animals and in humans. Recent findings not only proposed an CYP3A4-mediated degradation of vitamin E but also suggested an induction of the …
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Neurotransmitterfreisetzung und ihre präsynaptische Modulation im Hippocampus und anderen Gehirnstrukturen von Ratten nach Veränderungen im neuronalen Umfeld sowie in primären Neuronenkulturen
… oder im Alter vorkommen, zu Anpassungen der Transmitterfreisetzung in verbliebenen Neuronen? Dieser der vorliegenden Dissertation zugrundeliegenden Frage wurde anhand verschiedener Modelle nachgegangen. <br>Mit Hilfe eines Läsions-Transplantations-Modells des Hippocampus wurden drei an …
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Exploring the molecular mechanisms of AMPK-dependent regulation of neuroexcitability
… leads to voltage-gated calcium entry, exocytotic transmitter release and increases in carotid body afferent input responses that initiate corrective changes in breathing patterns. It was proposed that, in response to hypoxia, AMPK might directly phosphorylate and inhibit TASK channels, in …