Regulation of single spike initiated feed-forward networks through 5-HT-2 receptors in the human and rat cerebral cortex

Abstract

Event Abstract Back to Event Regulation of single spike initiated feed-forward networks through 5-HT-2 receptors in the human and rat cerebral cortex Gergely Komlosi1*, Gabor Molnar1, Noemi Molnar1, Szabolcs Olah1, Miklos Fule1, Pal Barzo2 and Gabor Tamas1 1 Research Group for Cortical Microcircuits of the Hungarian Academy of Sciences, University of Szeged, Hungary 2 Department of Neurosurgery, University of Szeged, Hungary The performance of the human cerebral cortex is unparalleled by the nervous system of other species and this is presumably supported by refined, but largely unknown features of the human microcircuit. We have shown that single action potentials in pyramidal cells can trigger reliable and stereotyped series of multiple postsynaptic potentials in simultaneously recorded pyramidal cells and interneurons in the human cerebral cortex. These polysynaptic event series are composed of alternating excitatory and inhibitory postsynaptic potentials lasting up to tens of milliseconds. We tested how these complex network events could be affected by ascending neurotransmitter systems. We recorded from pairs, triplets and quadruplets of neurons in slices of human association cortices and examined the effects of acetylcholine, dopamine and serotonin receptor agonists. Nanomolar concentrations of serotonin reversibly supressed single pyramidal spike activated di- and polysynaptic events, while other agonists exerted little or no effect. The effect of serotonin (100nM) could be enhanced by Fluoxetine used in therapeutic concentration (10M). Similarly, serotonin was effective in eliminating polysynaptic event series triggered by human axo-axonic cells. The effect of serotonin could be mimicked by the 5-HT-2 receptor agonist alpha-methylserotonin. We then investigated the effect of serotonin and alpha-methylserotonin on monosynaptic unitary connections between various types of layer 2/3 neurons both in human and rat. We found that alpha-methylserotonin decreased the amplitude of EPSPs between pyramidal and fast-spiking cells including basket and axo-axonic cells but did not change the amplitude of IPSPs from fast-spiking to pyramidal neurons. Alpha-methylserotonin increased the failure rate of the EPSPs suggesting a presynaptic site of modulation of serotonin in the glutamatergic synaptic transmission. In conclusion, activation of 5-HT2 receptors can eliminate pyramidal cell activated feed-forward network events presumably via downregulation of glutamate release probability in pyramidal axon terminals. Conference: 12th Meeting of the Hungarian Neuroscience Society, Budapest, Hungary, 22 Jan - 24 Jan, 2009. Presentation Type: Poster Presentation Topic: Research on the cerebral cortex and related structures Citation: Komlosi G, Molnar G, Molnar N, Olah S, Fule M, Barzo P and Tamas G (2009). Regulation of single spike initiated feed-forward networks through 5-HT-2 receptors in the human and rat cerebral cortex. Front. Syst. Neurosci. Conference Abstract: 12th Meeting of the Hungarian Neuroscience Society. doi: 10.3389/conf.neuro.01.2009.04.206 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: 06 Mar 2009; Published Online: 06 Mar 2009. * Correspondence: Gergely Komlosi, Research Group for Cortical Microcircuits of the Hungarian Academy of Sciences, University of Szeged, Szeged, Hungary, komgeri@bio.u-szeged.hu 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 Gergely Komlosi Gabor Molnar Noemi Molnar Szabolcs Olah Miklos Fule Pal Barzo Gabor Tamas Google Gergely Komlosi Gabor Molnar Noemi Molnar Szabolcs Olah Miklos Fule Pal Barzo Gabor Tamas Google Scholar Gergely Komlosi Gabor Molnar Noemi Molnar Szabolcs Olah Miklos Fule Pal Barzo Gabor Tamas PubMed Gergely Komlosi Gabor Molnar Noemi Molnar Szabolcs Olah Miklos Fule Pal Barzo Gabor Tamas 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.