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XXIII Congress of I.P. Pavlov Physiology Society
molecule production [1]. According to the experimental data the influence of ECM molecules on astrocytes is associated with the change in the number and properties of glial cells (specifically, changes in cellular morphology and intracellular pH [7]), which would in turn modulate the efficiency of neuron-glial interaction.
We present a computational model of neuronal network with tetrapartite synapse. The model describes the dynamics of excitatory and inhibitory neuron populations in the presence of glial and ECM regulations and based on mean-field approach. Neuron dynamics we modeled by Wilson-Cowan mean - field model [8]. The astrocyte is described by gliatransmitter concentrations depending on excitatory neuron population. We found that interaction between ECM, astrocytes and neuronal populations lead to spontaneous activity oscillations on extended timescales. The interaction parameters determine the oscillation period (hours to days) and their existence and switching to bistable regimes.
The research was supported by RFFI (#17-02-01103 A) References
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2. Kazantsev V, Gordleeva S, Stasenko S, Dityatev A. A homeostatic model of neuronal firing governed by feedback signals from the extracellular matrix. PLoS One. 2012;7: e41646. doi:10.1371/journal.pone.0041646
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6. Rich MM, Wenner P. Sensing and expressing homeostatic synaptic plasticity. Trends Neurosci. 2007;30: 119125. Available: http://www.ncbi.nlm.nih.gov/pubmed/17267052
7. Gottfried C, Cechin SR, Gonzalez MA, Vaccaro TS, Rodnight R. The influence of the extracellular matrix on the morphology and intracellular pH of cultured astrocytes exposed to media lacking bicarbonate. Neuroscience. 2003;121: 553-562. Available: http://linkinghub.elsevier.com/retrieve/pii/S0306452203005578
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Role of Extracellular Signaling in the Neocortical Development
Victor Tarabykin
Charité - Universitatsmedizin Berlin, Germany; UNN Institute of Neuroscience, Russia.
In the developing cerebral cortex different types of neuron and glial cells are born in a precise sequential manner from specialized radial glia progenitors. After leaving mitotic cycle, they migrate out of the germinative zone and initiate differentiation program. We identified a novel mechanism that controls cell identity in the developing cerebral cortex via "feedback" of secreted factors to neuronal progenitors. A defined set of secreted factors including neurotrophin-3, Sfrpl and Fgf9 were found to induce premature and excessive production of upper layer neurons at the expense of deep layer neurons on one hand and precocious generation of glial precursors on the other hand. This "feedback" is likely to act at the distal part of a radial glia process located in the area of young differentiating neurons. We suggest that various concentrations of secreted factors can be sensed by the radial glia process inducing cell fate switch. We identified non-canonical TrkC receptor as a major mediator of this extracellular signaling that controls cell fate switch in the developing neocortex.
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Opera Med Physiol 2017 Vol. 3 (S1) 11
