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Role of the synaptic microenvironment in functional modification of synaptic transmission

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Abstract

Experiments on hippocampal slices showed that perfusion with a dextran solution more effectively facilitates AMPA-mediated transmission in structurally complex synapses of mossy fibers of Shaffer collaterals. Estimates for changes in the extracellular Ca2+ concentration in the close vicinity of a reconstructed synapse during the action potential development are obtained. The results together with data about the rather small (0.5 μm) characteristics distance between neighboring synapses showed that the probability of mutual intersynaptic influence via the microenvironment is high. A probable functional role of such influences is discussed.

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Rusakov, D.A., Min, MY., Skibo, G.G. et al. Role of the synaptic microenvironment in functional modification of synaptic transmission. Neurophysiology 31, 79–81 (1999). https://doi.org/10.1007/BF02515039

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