Dynamic-Clamp pp 165-197 | Cite as

Functions of the Persistent Na+ Current in Cortical Neurons Revealed by Dynamic Clamp

Part of the Springer Series in Computational Neuroscience book series (NEUROSCI, volume 1)


Many cortical neurons and other vertebrate nerve cells are equipped with a persistent Na+ current, I NaP, which operates at membrane potentials near the action potential threshold. This current may strongly influence integration and transduction of synaptic input into spike patterns. However, due to the lack of pharmacological tools for selective blockade or enhancement of I NaP, its impact on spike generation has remained enigmatic. By using dynamic clamp to cancel or add I NaP during intracellular recordings in rat hippocampal pyramidal cells, we were able to circumvent this long-standing problem. Combined with computational modeling our dynamic-clamp experiments disclosed how I NaP strongly affects the transduction of excitatory current into action potentials in these neurons. First, we used computational model simulations to predict functional roles of I NaP, including unexpected effects on spike timing and current–frequency relations. We then used the dynamic-clamp technique to experimentally test and confirm our model predictions.


Pyramidal Neuron Axon Initial Segment Repetitive Firing Spike Threshold Subthreshold Oscillation 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



Our work was supported by the Norwegian Research Council (NFR) through FUGE, NevroNor, and the Norwegian Centre of Excellence programs, and by HFSP for Research Grant RGP0049 to L.J.G. and J.F.S.


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© Springer Science+Business Media, LLC 2009

Authors and Affiliations

  1. 1.Department of Physiology at Institute of Basal Medicine, and Centre of Molecular Biology and NeuroscienceUniversity of OsloPB 1103 BlindernNorway

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