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- Open Access
Axon initial segment potassium channel density in cortical neurons
© Zhang et al. 2015
- Published: 18 December 2015
- Cortical Neuron
- Intrinsic Factor
- Action Potential Duration
- GABAergic Interneuron
- Axon Initial Segment
There is a growing interest in estimating actual density ranges of Na+ channels in the very thin axon, especially in the action potential (AP) initiation zone, i.e., the axon initial segment (AIS, 20-50 microns away from the cell body). Both immunostaining studies and patch-clamp recordings indicated a relatively high density of Na+ channels in AIS of either pyramidal regular-spiking (RS) cells  or fast-spiking (FS) GABAergic interneurons [2, 3]. Here, we investigated potassium channel densities in AISs of both RS and FS cells in same recording conditions.
In sum, the significant difference in potassium channel density in axonal initial segment where action potentials are initiated may play a critical role in controlling action potential properties of both RS- and FS-spiking cells in nervous system by the same general biophysical rule. These results may be important for constructing computational models of different types of cortical neurons.
This project is funded by NNSF of China (31271170) and Eastern Scholar SHH1140004) at Shanghai Institutions of Higher Learning.
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