Nature Neuroscience5, 1185 - 1193 (2002)
Published online: 21 October 2002; | doi:10.1038/nn962
Polarized and compartment-dependent distribution of HCN1 in pyramidal cell dendrites
Andrea Lörincz1, 2, Takuya Notomi3, Gábor Tamás2, Ryuichi Shigemoto3
& Zoltan Nusser1
1
Laboratory of Cellular Neurophysiology, Institute of Experimental Medicine, Hungarian Academy of Sciences Szigony Street 43, 1083 Budapest, Hungary
2
Department of Comparative Physiology, University of Szeged, Közép fasor 52, 6726 Szeged, Hungary
3
Division of Cerebral Structure, National Institute for Physiological Sciences, The Graduate University for Advanced Studies, School of Life Science, Okazaki, CREST Japan Science and Technology Corporation, Kawaguchi, Okazaki 444-8585, Japan
Correspondence should be addressed to Zoltan Nusser nusser@koki.hu
An ion channel's function depends largely on its location and density on neurons. Here we used high-resolution immunolocalization to determine the subcellular distribution of the hyperpolarization-activated and cyclic-nucleotide-gated channel subunit 1 (HCN1) in rat brain. Light microscopy revealed graded HCN1 immunoreactivity in apical dendrites of hippocampal, subicular and neocortical layer-5 pyramidal cells. Quantitative comparison of immunogold densities showed a 60-fold increase from somatic to distal apical dendritic membranes. Distal dendritic shafts had 16 times more HCN1 labeling than proximal dendrites of similar diameters. At the same distance from the soma, the density of HCN1 was significantly higher in dendritic shafts than in spines. Our results reveal the complex cell surface distribution of voltage-gated ion-channels, and predict its role in increasing the computational power of single neurons via subcellular domain and input-specific mechanisms.
