NMDA Receptors Enhance the Fidelity of Synaptic Integration

Abstract Excitatory synaptic transmission in many neurons is mediated by two coexpressed ionotropic glutamate receptor subtypes, AMPA and NMDA receptors, that differ kinetics, ion selectivity, voltage-sensitivity. receptors have fast kinetics are voltage-insensitive, while slower increased conductance at depolarized membrane potentials. Here, we report the voltage dependency of act synergistically to stabilize integration EPSPs across spatial domains. Simulations simplified morphologically realistic dendritic trees revealed combined presence conductances reduce variability somatic responses spatiotemporal patterns excitatory input presented different initial potentials and/or This moderating effect on was robust a wide range AMPA-to-NMDA ratios, results from synergistic interaction (which reduces potential) dependence favors stabilization location). When with conductance, compensates for voltage-dependent impedance-dependent changes driving force, distance-dependent attenuation arriving axon, increase fidelity EPSP-spike coupling both neuron state (i.e., location input. Thus, convey advantages independent of, but fully compatible with, their importance coincidence detection plasticity.