Hyperpolarization-activated cation current Ih influences synaptic integration properties in substantia nigra dopamine neurons

Abstract

Event Abstract Back to Event Hyperpolarization-activated cation current Ih influences synaptic integration properties in substantia nigra dopamine neurons Dominique Engel1* and Vincent Seutin2 1 FNRS, GIGA-Neurosciences, Belgium 2 Université de Liège, GIGA-Neuroscience, Belgium The hyperpolarization-activated cation current Ih is expressed in many pyramidal neurons and in some interneurons. Ih contributes to neuronal signaling via the modulation of passive and active membrane properties, intrinsic resonance, synaptic integration and synaptic plasticity. One of the most characteristic functions of Ih is to influence synaptic integration by inducing a location independence of postsynaptic potentials (EPSPs) waveform and EPSP temporal summation. Herewith, EPSPs arriving at the soma have a similar time course, regardless of their origin. In pyramidal neurons, this effect of Ih is correlated to a specific subcellular distribution of the channel. In the substantia nigra, dopamine (DA) neurons are implicated in the control of movement. Their degeneration is related to motor disturbances as they are described in Parkinson’s disease. Interestingly, the axon of DA neurons generally emerges from a dendrite dividing the dendritic compartment of these neurons in axon- and non-axon bearing dendrites. This morphology contrasts with the typical arrangement of subcellular compartments found in neurons. DA neurons are also well known to display a prominent sag in response to long hyperpolarizing current injections, consecutive to slowly activating h-channels. However, the subcellular distribution of the channel and its role in synaptic integration is unknown for DA neurons. We performed cell-attached patch-clamp recordings along the somatodendritic domain of DA neurons and observed a high Ih current density in the axon-bearing dendrites in a membrane region close to the axon origin. Simultaneous whole-cell somatic and dendritic recordings revealed that Ih reduces EPSP integral and temporal summation. Keywords: Dopamine Neuron, Substantia Nigra, Dendrites, integration properties, hyperpolarization-activated inwardly rectifying cation conductance, Ih Conference: 11th National Congress of the Belgian Society for Neuroscience, Mons, Belgium, 22 May - 22 May, 2015. Presentation Type: Poster presentation Topic: Neuroscience Citation: Engel D and Seutin V (2015). Hyperpolarization-activated cation current Ih influences synaptic integration properties in substantia nigra dopamine neurons. Front. Neurosci. Conference Abstract: 11th National Congress of the Belgian Society for Neuroscience. doi: 10.3389/conf.fnins.2015.89.00016 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 05 May 2015; Published Online: 05 May 2015. * Correspondence: Dr. Dominique Engel, FNRS, GIGA-Neurosciences, Liege, 4000, Belgium, dominique.engel@uliege.be Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Dominique Engel Vincent Seutin Google Dominique Engel Vincent Seutin Google Scholar Dominique Engel Vincent Seutin PubMed Dominique Engel Vincent Seutin Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.