Type 1 cannabinoid receptor (CB1)-containing axons innervate magnocellular vasopressin-synthesizing neurons in the hypothalamic paraventricular nucleus in mice

Abstract

Event Abstract Back to Event Type 1 cannabinoid receptor (CB1)-containing axons innervate magnocellular vasopressin-synthesizing neurons in the hypothalamic paraventricular nucleus in mice Z. Bardóczi1, A. Kádár1, M. Watanabe2, Z. Liposits3, C. Fekete1 and I. Kalló1* 1 Institute of Experimental Medicine, Hungarian Academy of Sciences, Department of Endocrine Neurobiology, Hungary 2 Hokkaido University School of Medicine, Department of Anatomy, Japan 3 Pázmány Péter Catholic University, Department of Neuroscience, Hungary The magnocellular vasopressin-synthesizing neurons of the hypothalamic paraventricular nucleus (PVN) play critical role in the regulation of fluid balance and blood pressure. Recently, the retrograde signaling endocannabinoid system has been shown to exert inhibitory effects on magnocellular neurons via type 1 cannabinoid receptor (CB1). To understand the anatomical basis for this regulatory mechanism, we determined whether CB1 is contained in axons innervating vasopressin-immunoreactive (IR) neurons.At the light microscopic level dense CB1-IR axon network was observed in the PVN. The CB1-IR innervation had punctuated appearance and was the densest in the posterior part of the PVN. In the compact part, at the mid level of the nucleus, where the vasopressin neurons reside, the density of the innervation was relatively lower. However, in double-labeled preparations, CB1-IR varicosities were observed in juxtaposition to the majority of the magnocellular vasopressin neurons. At the electron microscopic level, CB1-immunoreactivity was observed in the pre-terminal portion of axons establishing both symmetric and asymmetric synaptic specializations with the perikaryon and dendrites of vasopressin-IR neurons in the PVN. These data demonstrate that CB1 is abundantly present in both the excitatory and inhibitory axons that are in synaptic association with vasopressin-IR neurons indicating that these neurons can regulate their own input through the endocannabinoid system. Acknowledgements This work was supported by OTKA K69127, T73002, K83710; ETT 122/2009; FP7/2007-2013; grant agreement n° 245009. Keywords: Neuroendocrinology, Neuroscience Conference: 13th Conference of the Hungarian Neuroscience Society (MITT), Budapest, Hungary, 20 Jan - 22 Jan, 2011. Presentation Type: Abstract Topic: Neuroendocrinology Citation: Bardóczi Z, Kádár A, Watanabe M, Liposits Z, Fekete C and Kalló I (2011). Type 1 cannabinoid receptor (CB1)-containing axons innervate magnocellular vasopressin-synthesizing neurons in the hypothalamic paraventricular nucleus in mice. Front. Neurosci. Conference Abstract: 13th Conference of the Hungarian Neuroscience Society (MITT). doi: 10.3389/conf.fnins.2011.84.00091 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: 03 Mar 2011; Published Online: 23 Mar 2011. * Correspondence: Dr. I. Kalló, Institute of Experimental Medicine, Hungarian Academy of Sciences, Department of Endocrine Neurobiology, Budapest, Hungary, kallo@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 Z. Bardóczi A. Kádár M. Watanabe Z. Liposits C. Fekete I. Kalló Google Z. Bardóczi A. Kádár M. Watanabe Z. Liposits C. Fekete I. Kalló Google Scholar Z. Bardóczi A. Kádár M. Watanabe Z. Liposits C. Fekete I. Kalló PubMed Z. Bardóczi A. Kádár M. Watanabe Z. Liposits C. Fekete I. Kalló 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.