" ... Here we show that the voltage fluctuations associated with dendrosomatic synaptic activity propagate significant distances along the axon, and that modest changes in the somatic membrane potential of the presynaptic neuron modulate the amplitude and duration of axonal action potentials and, through a Ca21- dependent mechanism, the average amplitude of the postsynaptic potential evoked by these spikes. These results indicate that synaptic activity in the dendrite and soma controls not only the pattern of action potentials generated, but also the amplitude of the synaptic potentials that these action potentials initiate in local cortical circuits, resulting in synaptic transmission that is a mixture of triggered and graded (analogue) signals."
Model Type: Neuron or other electrically excitable cell; Axon
Cell Type(s): Neocortex L5/6 pyramidal GLU cell
Currents: I Na,t; I L high threshold; I A; I K; I M; I h; I K,Ca; I_AHP; I_KD
Model Concept(s): Action Potential Initiation; Detailed Neuronal Models; Action Potentials; Synaptic Integration
Simulation Environment: NEURON
References:
Shu Y, Duque A, Yu Y, Haider B, McCormick DA. (2007). Properties of action-potential initiation in neocortical pyramidal cells: evidence from whole cell axon recordings. Journal of neurophysiology. 97 [PubMed]
Shu Y, Hasenstaub A, Duque A, Yu Y, McCormick DA. (2006). Modulation of intracortical synaptic potentials by presynaptic somatic membrane potential. Nature. 441 [PubMed]