Submitted through the Neuroscience Peer Review Consortium (NPRC) framework.
Unique somato-dendritic distribution pattern of Kv4.2 channels on hippocampal CA1 pyramidal cells
Article first published online: 18 NOV 2011
© 2011 The Authors. European Journal of Neuroscience © 2011 Federation of European Neuroscience Societies and Blackwell Publishing Ltd
European Journal of Neuroscience
Volume 35, Issue 1, pages 66–75, January 2012
How to Cite
Kerti, K., Lorincz, A. and Nusser, Z. (2012), Unique somato-dendritic distribution pattern of Kv4.2 channels on hippocampal CA1 pyramidal cells. European Journal of Neuroscience, 35: 66–75. doi: 10.1111/j.1460-9568.2011.07907.x
Re-use of this article is permitted in accordance with the Terms and Conditions set out at http://wileyonlinelibrary.com/onlineopen#OnlineOpen_Terms
- Issue published online: 2 JAN 2012
- Article first published online: 18 NOV 2011
- Received 13 September 2011, revised 14 September 2011, accepted 15 September 2011
- potassium channels;
- pyramidal cell;
A-type K+ current (IA) plays a critical role in controlling the excitability of pyramidal cell (PC) dendrites. In vitro dendritic patch-pipette recordings have demonstrated a prominent, sixfold increase in IA density along the main apical dendrites of rat hippocampal CA1 PCs. In these cells, IA is mediated by Kv4.2 subunits, whose precise subcellular distribution and densities in small-diameter oblique dendrites and dendritic spines are still unknown. Here we examined the densities of the Kv4.2 subunit in 13 axo-somato-dendritic compartments of CA1 PCs using a highly sensitive, high-resolution quantitative immunogold localization method (sodium dodecyl sulphate-digested freeze-fracture replica-labelling). Only an approximately 70% increase in Kv4.2 immunogold density was observed along the proximo-distal axis of main apical dendrites in the stratum radiatum with a slight decrease in density in stratum lacunosum-moleculare. A similar pattern was detected for all dendritic compartments, including main apical dendrites, small-diameter oblique dendrites and dendritic spines. The specificity of the somato-dendritic labelling was confirmed in Kv4.2−/− tissue. No specific immunolabelling for the Kv4.2 subunit was found in SNAP-25-containing presynaptic axons. Our results demonstrate a novel distribution pattern of a voltage-gated ion channel along the somato-dendritic surface of CA1 PCs, and suggest that the increase in the IA along the proximo-distal axis of PC dendrites cannot be solely explained by a corresponding increase in Kv4.2 channel number.