The relative contribution of NMDARs to excitatory postsynaptic currents is controlled by Ca2+-induced inactivation
NMDA receptors (NMDARs) are important mediators of excitatory synaptic transmission and plasticity. A hallmark of these channels is their high permeability to Ca2+. At the same time, they are themselves inhibited by the elevation of intracellular Ca2+ concentration. It is unclear however, whether th...
Saved in:
| Main Authors: | , , , , , |
|---|---|
| Format: | Article (Journal) |
| Language: | English |
| Published: |
29 January 2016
|
| In: |
Frontiers in cellular neuroscience
Year: 2016, Volume: 10, Pages: 1-10 |
| ISSN: | 1662-5102 |
| DOI: | 10.3389/fncel.2016.00012 |
| Online Access: | Verlag, kostenfrei, Volltext: https://doi.org/10.3389/fncel.2016.00012 Verlag, kostenfrei, Volltext: https://www.frontiersin.org/articles/10.3389/fncel.2016.00012/full 
|
| Author Notes: | Fliza Valiullina, Yulia Zakharova, Marat Mukhtarov, Andreas Draguhn, Nail Burnashev and Andrei Rozov |
| Summary: | NMDA receptors (NMDARs) are important mediators of excitatory synaptic transmission and plasticity. A hallmark of these channels is their high permeability to Ca2+. At the same time, they are themselves inhibited by the elevation of intracellular Ca2+ concentration. It is unclear however, whether the Ca2+ entry associated with single NMDAR mediated synaptic events is sufficient to self-inhibit their activation. Such auto-regulation would have important effects on the dynamics of synaptic excitation in several central networks. Therefore, we studied NMDAR-mediated synaptic currents in mouse hippocampal CA1 pyramidal neurons. Postsynaptic responses to subthreshold Schaffer collateral stimulation depended strongly on the absence or presence of intracellular Ca2+ buffers. Loading of pyramidal cells with exogenous Ca2+ buffers increased the amplitude and decay time of NMDAR mediated EPSCs (EPSP) and prolonged the time window for action potential generation. Our data indicate that the Ca2+ influx mediated by unitary synaptic events is sufficient to produce detectable self-inhibition of NMDARs even at a physiological Mg2+ concentration. Therefore, the contribution of NMDARs to synaptic excitation is strongly controlled by both previous synaptic activity as well as by the Ca2+ buffer capacity of postsynaptic neurons. |
|---|---|
| Item Description: | 2+ im Titel ist hochgestellt Gesehen am 29.05.2020 |
| Physical Description: | Online Resource |
| ISSN: | 1662-5102 |
| DOI: | 10.3389/fncel.2016.00012 |