Summary
Neocortical neurons have a tetrodotoxin (TTX) sensitive noninactivating current. Whole cell voltage clamp shows this current is activated about 10 mV negative to spike threshold. On-cell patches show transient sodium channels that fail to activate in less than 1% of the depolarizations which is compatible with the magnitude of the persistent cuurrent. This rare modal change in inactivation provides the cell with a small persistent current mechanism that amplifies depolarizing synaptic currents. Its presence in dendrites effectively shortens the electrical length of the dendrites.
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© 1996 Birkhäuser Verlag Basel/Switzerland
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Crill, W.E. (1996). The functional role of a noninactivating sodium current in neocortical neurons. In: Franzén, O., Johansson, R., Terenius, L. (eds) Somesthesis and the Neurobiology of the Somatosensory Cortex. Advances in Life Sciences. Birkhäuser Basel. https://doi.org/10.1007/978-3-0348-9016-8_4
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DOI: https://doi.org/10.1007/978-3-0348-9016-8_4
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