Subthreshold depolarization of soma passively propagates into the axons for a substantial distance and thereby caused enhancement of the transmitter release from the axon terminals of hippocampal mossy fibers. Here we developed the granule cell-mossy fiber model implemented with axonal sodium potassium and calcium channels and explored the mechanisms underlying analog modulation of the action potential-evoked transmitter release by subthreshold voltage signaling along the axons. Action potential-induced calcium entry to the terminals was reduced, while subthreshold depolarization itself caused small calcium entry.
Model Type: Axon
Region(s) or Organism(s): Hippocampus
Cell Type(s): Dentate gyrus granule GLU cell
Currents: I Calcium; I Sodium; I K
Model Concept(s): Action Potentials; Axonal Action Potentials; Analog coding; Subthreshold signaling
Simulation Environment: NEURON
Implementer(s): Kamiya, Haruyuki [kamiya at med.hokudai.ac.jp]
References:
Kamiya H. (2022). Modeling analysis of subthreshold voltage signaling along hippocampal mossy fiber axons Front Cell Neurosci.