Event Abstract Back to Event Synaptic organization of retrograde 2-arachidonoylglycerol signaling in the dorsolateral periaqueductal grey matter Rita Nyilas1*, Laura C. Gregg2, Jessica M. Spradley2, Ken Mackie3, Andrea G. Hohmann2 and István Katona1 1 Hungarian Academy of Sciences, Institute of Experimental Medicine, Hungary 2 University of Georgia, United States 3 Indiana University, United States The striking antinociceptive effect of cannabinoid receptor agonists in acute nociception and chronic pain states is well-documented. 2-arachidonoylglycerol (2-AG), an endogenous ligand for both CB1 and CB2 cannabinoid receptors and a candidate retrograde synaptic endocannabinoid in the brain, has been implicated in the physiological regulation of nociception. However, the molecular machinery of synaptic 2-AG signaling involved has not been identified in the periaqueductal grey matter (PAG), a key midbrain area in the descending control of pain. To uncover the molecular architecture of 2-AG synthesis and identify sites of 2-AG action, we examined the detailed anatomical distribution of diacylglycerol lipase-α (DGL-α), metabotropic glutamate receptor 5 (mGluR5) and the CB1 cannabinoid receptor in the rodent dorsolateral (dl) PAG. Using peroxidase-based immunocytochemistry, dense distribution of DGL-α enzyme and CB1 receptor was revealed at the light microscopic level. Immunogold labeling followed by high-resolution electron microscopy showed that DGL-α, the main biosynthetic enzyme of 2-AG, was located in a remarkable postsynaptic position and co-localized with metabotropic glutamate receptor 5 (mGluR5), an upstream activator of 2-AG biosynthesis, while CB1 was found presynaptically on axon terminals. This striking positioning of DGL-α and CB1 were found at both excitatory and inhibitory synapses of the dl PAG. These findings imply a key role of the retrograde 2-AG pathway, present in dl PAG neuronal synapses, in the activity-dependent regulation of nociception. Conference: IBRO International Workshop 2010, Pécs, Hungary, 21 Jan - 23 Jan, 2010. Presentation Type: Poster Presentation Topic: Cellular neuroscience Citation: Nyilas R, Gregg LC, Spradley JM, Mackie K, Hohmann AG and Katona I (2010). Synaptic organization of retrograde 2-arachidonoylglycerol signaling in the dorsolateral periaqueductal grey matter. Front. Neurosci. Conference Abstract: IBRO International Workshop 2010. doi: 10.3389/conf.fnins.2010.10.00112 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 Apr 2010; Published Online: 23 Apr 2010. * Correspondence: Rita Nyilas, Hungarian Academy of Sciences, Institute of Experimental Medicine, Budapest, Hungary, nyilasr@koki.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 Rita Nyilas Laura C Gregg Jessica M Spradley Ken Mackie Andrea G Hohmann István Katona Google Rita Nyilas Laura C Gregg Jessica M Spradley Ken Mackie Andrea G Hohmann István Katona Google Scholar Rita Nyilas Laura C Gregg Jessica M Spradley Ken Mackie Andrea G Hohmann István Katona PubMed Rita Nyilas Laura C Gregg Jessica M Spradley Ken Mackie Andrea G Hohmann István Katona 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.