Functional compensation of P/Q by N-type channels blocks short-term plasticity at the calyx of Held presynaptic terminal

Calcium channels of the P/Q subtype mediate transmitter release at the neuromuscular junction and at many central synapses, such as the calyx of Held. Transgenic mice in which α1A channels are ablated provide a powerful tool with which to test compensatory mechanisms at the synapse and to explore me...

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Autores principales: González Inchauspe, Carlota María Fabiola, Uchitel, Osvaldo Daniel
Publicado: 2004
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Acceso en línea:https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_02706474_v24_n46_p10379_GonzalezInchauspe
http://hdl.handle.net/20.500.12110/paper_02706474_v24_n46_p10379_GonzalezInchauspe
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spelling paper:paper_02706474_v24_n46_p10379_GonzalezInchauspe2023-06-08T15:24:45Z Functional compensation of P/Q by N-type channels blocks short-term plasticity at the calyx of Held presynaptic terminal González Inchauspe, Carlota María Fabiola Uchitel, Osvaldo Daniel Calcium currents Calyx of Held Facilitation Knock-out mice P/Q channels Synaptic transmission calcium channel N type calcium channel P type calcium channel Q type calcium ion animal tissue article calcium current channel gating facilitation knockout mouse mouse nerve cell plasticity nonhuman presynaptic membrane priority journal synaptosome transgenic mouse Animals Brain Stem Calcium Calcium Channels, N-Type Calcium Channels, P-Type Calcium Channels, Q-Type Evoked Potentials Mice Mice, Knockout Neuronal Plasticity Presynaptic Terminals Protein Subunits Synapses Synaptic Transmission Calcium channels of the P/Q subtype mediate transmitter release at the neuromuscular junction and at many central synapses, such as the calyx of Held. Transgenic mice in which α1A channels are ablated provide a powerful tool with which to test compensatory mechanisms at the synapse and to explore mechanisms of presynaptic regulation associated with expression of P/Q channels. Using the calyx of Held preparation from the knock-out (KO) mice, we show here that N-type channels functionally compensate for the absence of P/Q subunits at the calyx and evoke giant synaptic currents [approximately two-thirds of the magnitude of wild-type (WT) responses]. However, although evoked paired-pulse facilitation is prominent in WT, this facilitation is greatly diminished in the KO. In addition, direct recording of presynaptic calcium currents revealed that the major functional difference was the absence of calcium-dependent facilitation at the calyx in the P/Q KO animals. We conclude that one physiological function of P/Q channels is to provide additional facilitatory drive, so contributing to maintenance of transmission as vesicles are depleted during high throughput synaptic transmission. Fil:González Inchauspe, C. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Uchitel, O.D. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. 2004 https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_02706474_v24_n46_p10379_GonzalezInchauspe http://hdl.handle.net/20.500.12110/paper_02706474_v24_n46_p10379_GonzalezInchauspe
institution Universidad de Buenos Aires
institution_str I-28
repository_str R-134
collection Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA)
topic Calcium currents
Calyx of Held
Facilitation
Knock-out mice
P/Q channels
Synaptic transmission
calcium channel N type
calcium channel P type
calcium channel Q type
calcium ion
animal tissue
article
calcium current
channel gating
facilitation
knockout mouse
mouse
nerve cell plasticity
nonhuman
presynaptic membrane
priority journal
synaptosome
transgenic mouse
Animals
Brain Stem
Calcium
Calcium Channels, N-Type
Calcium Channels, P-Type
Calcium Channels, Q-Type
Evoked Potentials
Mice
Mice, Knockout
Neuronal Plasticity
Presynaptic Terminals
Protein Subunits
Synapses
Synaptic Transmission
spellingShingle Calcium currents
Calyx of Held
Facilitation
Knock-out mice
P/Q channels
Synaptic transmission
calcium channel N type
calcium channel P type
calcium channel Q type
calcium ion
animal tissue
article
calcium current
channel gating
facilitation
knockout mouse
mouse
nerve cell plasticity
nonhuman
presynaptic membrane
priority journal
synaptosome
transgenic mouse
Animals
Brain Stem
Calcium
Calcium Channels, N-Type
Calcium Channels, P-Type
Calcium Channels, Q-Type
Evoked Potentials
Mice
Mice, Knockout
Neuronal Plasticity
Presynaptic Terminals
Protein Subunits
Synapses
Synaptic Transmission
González Inchauspe, Carlota María Fabiola
Uchitel, Osvaldo Daniel
Functional compensation of P/Q by N-type channels blocks short-term plasticity at the calyx of Held presynaptic terminal
topic_facet Calcium currents
Calyx of Held
Facilitation
Knock-out mice
P/Q channels
Synaptic transmission
calcium channel N type
calcium channel P type
calcium channel Q type
calcium ion
animal tissue
article
calcium current
channel gating
facilitation
knockout mouse
mouse
nerve cell plasticity
nonhuman
presynaptic membrane
priority journal
synaptosome
transgenic mouse
Animals
Brain Stem
Calcium
Calcium Channels, N-Type
Calcium Channels, P-Type
Calcium Channels, Q-Type
Evoked Potentials
Mice
Mice, Knockout
Neuronal Plasticity
Presynaptic Terminals
Protein Subunits
Synapses
Synaptic Transmission
description Calcium channels of the P/Q subtype mediate transmitter release at the neuromuscular junction and at many central synapses, such as the calyx of Held. Transgenic mice in which α1A channels are ablated provide a powerful tool with which to test compensatory mechanisms at the synapse and to explore mechanisms of presynaptic regulation associated with expression of P/Q channels. Using the calyx of Held preparation from the knock-out (KO) mice, we show here that N-type channels functionally compensate for the absence of P/Q subunits at the calyx and evoke giant synaptic currents [approximately two-thirds of the magnitude of wild-type (WT) responses]. However, although evoked paired-pulse facilitation is prominent in WT, this facilitation is greatly diminished in the KO. In addition, direct recording of presynaptic calcium currents revealed that the major functional difference was the absence of calcium-dependent facilitation at the calyx in the P/Q KO animals. We conclude that one physiological function of P/Q channels is to provide additional facilitatory drive, so contributing to maintenance of transmission as vesicles are depleted during high throughput synaptic transmission.
author González Inchauspe, Carlota María Fabiola
Uchitel, Osvaldo Daniel
author_facet González Inchauspe, Carlota María Fabiola
Uchitel, Osvaldo Daniel
author_sort González Inchauspe, Carlota María Fabiola
title Functional compensation of P/Q by N-type channels blocks short-term plasticity at the calyx of Held presynaptic terminal
title_short Functional compensation of P/Q by N-type channels blocks short-term plasticity at the calyx of Held presynaptic terminal
title_full Functional compensation of P/Q by N-type channels blocks short-term plasticity at the calyx of Held presynaptic terminal
title_fullStr Functional compensation of P/Q by N-type channels blocks short-term plasticity at the calyx of Held presynaptic terminal
title_full_unstemmed Functional compensation of P/Q by N-type channels blocks short-term plasticity at the calyx of Held presynaptic terminal
title_sort functional compensation of p/q by n-type channels blocks short-term plasticity at the calyx of held presynaptic terminal
publishDate 2004
url https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_02706474_v24_n46_p10379_GonzalezInchauspe
http://hdl.handle.net/20.500.12110/paper_02706474_v24_n46_p10379_GonzalezInchauspe
work_keys_str_mv AT gonzalezinchauspecarlotamariafabiola functionalcompensationofpqbyntypechannelsblocksshorttermplasticityatthecalyxofheldpresynapticterminal
AT uchitelosvaldodaniel functionalcompensationofpqbyntypechannelsblocksshorttermplasticityatthecalyxofheldpresynapticterminal
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