Open AccessInteractions among diameter, myelination, and the Na/K pump affect axonal resilience to high-frequency spiking
Author(s) -
Yunliang Zang,
Eve Marder
Publication year - 2021
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.2105795118
Subject(s) - biophysics , gating , neuroscience , axon , physics , chemistry , electrophysiology , biology
Significance The reliability of spike propagation in axons is determined by complex interactions among ionic currents, ion pumps, and morphological properties. We use compartment-based modeling to reveal that interactions of diameter, myelination, and the Na/K pump determine the reliability of high-frequency spike propagation. By acting as a “reservoir” of nodal Na+ influx, myelinated compartments efficiently increase propagation reliability. Although spike broadening was thought to oppose fast spiking, its effect on spike propagation is complicated, depending on the balance of Na+ channel inactivation gate recovery, Na+ influx, and axial charge. Our findings suggest that slow Na+ removal influences axonal resilience to high-frequency spike propagation and that different strategies may be required to overcome this constraint in different neurons.