A GABAergic fingerprint identifies stress-susceptibility versus resilience in a chronic mild stress rat model of depression

Abstract

Event Abstract Back to Event A GABAergic fingerprint identifies stress-susceptibility versus resilience in a chronic mild stress rat model of depression M. Holm1*, K. Jensen1, 2, J. Nieto-Gonzalez1, I. Vardya1 and O. Wiborg2 1 Aarhus University, Synaptic Physiology Laboratory, Department of Physiology and Biophysics, Denmark 2 Aarhus University Hospital, Centre for Psychiatric Research, Denmark It is known that GABAergic hippocampal synapses display short-term synaptic plasticity, i.e. an activity-dependent change in neurotransmitter release during repeated activation. Here we tested whether such synaptic plasticity could be correlated with the behavioral readouts in the chronic mild stress model of depression. Adult male rats were exposed to an eight week long chronic mild stress protocol leading to an anhedonic-like behavior. 350 µm thick ventral horizontal brain slices were prepared for electrophysiological recordings. Spontaneous and evoked inhibitory postsynaptic currents (IPSCs) were recorded in dentate gyrus granule cells. In controls, evoked GABAergic IPSCs showed a paired-pulse ratio (PPR) of 0.81 ± 0.05 (n = 24 cells / 6 rats). In contrast, in stress-susceptible rats the evoked GABAergic IPSCs showed a PPR of 1.26 ± 0.1 (n = 22 cells / 6 rats). Stress-resilient rats showed a paired-pulse ratio which was not significantly different from control rats (PPR of 0.78 ± 0.03 (n = 19 cells / 6 rats)). The GABAB receptor antagonist CGP55845 (5 µM) had no effect on the paired-pulse ratio in any of the groups. Postsynaptically, there were no changes in the frequency and decay kinetics of miniature IPSCs. We propose that stress-susceptibility in rats is associated with presynaptic changes, which may be due to alterations in the presynaptic release machinery, including its complex protein and vesicle composition. Notably, this is the first demonstration of an electrophysiological fingerprint clearly distinguishing stress-susceptible from stress-resilient rats in this model, which indicates that stress-susceptibility is linked to a distinct hippocampal synaptopathy. Conference: EMBO workshop: Gaba Signalling and Brain Networks , Amsterdam, Netherlands, 30 Jun - 2 Jul, 2010. Presentation Type: Poster Presentation Topic: Posters Citation: Holm M, Jensen K, Nieto-Gonzalez J, Vardya I and Wiborg O (2010). A GABAergic fingerprint identifies stress-susceptibility versus resilience in a chronic mild stress rat model of depression. Conference Abstract: EMBO workshop: Gaba Signalling and Brain Networks . doi: 10.3389/conf.fnins.2010.15.00010 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: 23 Jun 2010; Published Online: 23 Jun 2010. * Correspondence: M. Holm, Aarhus University, Synaptic Physiology Laboratory, Department of Physiology and Biophysics, Aarhus, Denmark, mmh@biomed.au.dk 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 M. Holm K. Jensen J. Nieto-Gonzalez I. Vardya O. Wiborg Google M. Holm K. Jensen J. Nieto-Gonzalez I. Vardya O. Wiborg Google Scholar M. Holm K. Jensen J. Nieto-Gonzalez I. Vardya O. Wiborg PubMed M. Holm K. Jensen J. Nieto-Gonzalez I. Vardya O. Wiborg 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.