Neurochemical Characterization of Connections between Commissural Interneurons and Motoneurons in the Spinal Cord of Neonatal Rat

Abstract

Event Abstract Back to Event Neurochemical Characterization of Connections between Commissural Interneurons and Motoneurons in the Spinal Cord of Neonatal Rat András Birinyi1*, Ildiko Weber1, Gabor Veres1 and Miklos Antal1 1 Department of Anatomy, University of Debrecen, Hungary Commissural interneurons (CINs) are located in the ventromedial area of the spinal cord and play an important role for left-right alternation of limbs during walking. We have carried out two series of experiments to investigate morphological and neurochemical properties of connections between commissural interneurons and motoneurons. In the first experiment BDA was injected into the ventromedial gray matter of the lumbar spinal cord and the motoneurons were labeled on the opposite side by applying biocytin onto the ventral roots. We found 291 close appositions between commissural axon terminals and the cell bodies and dendritic trees of 632 investigated motor neurons. Individual motor neurons received 1 to 3 contacts. The axo-dendritic and axo-somatic synapses were also verified at electron microscopic level from ultrathin sections of close appositions. In our second experiment commissural interneurons were revealed by injection of rhodamine dextran amine and contralateral motoneurons were labeled with neurobiotin. The neurotransmitters in the labeled axon terminals were identified by applying VGLUT1,2 and GAD65/67 antibodies and were investigated in confocal microscope. Out of 2679 CIN axon terminals 426 (16%) proved to be glutamatergic and 71of these excitatory terminals established monosynaptic contacts with contralateral motoneurons. Out of 4570 labeled boutons about 1207 (26 %) were immunoreactive for GAD and 17% of these inhibitory terminals made close appositions with the motoneurons. We concluded that crossed coordination of hindlimbs is partially mediated by monosynaptic excitatory and inhibitory connections between CINs and motor neurons. This work was supported by OTKA K67747 and ETT 025/2006. Conference: 12th Meeting of the Hungarian Neuroscience Society, Budapest, Hungary, 22 Jan - 24 Jan, 2009. Presentation Type: Poster Presentation Topic: Developmental neurobiology and subcortical functions Citation: Birinyi A, Weber I, Veres G and Antal M (2009). Neurochemical Characterization of Connections between Commissural Interneurons and Motoneurons in the Spinal Cord of Neonatal Rat. Front. Syst. Neurosci. Conference Abstract: 12th Meeting of the Hungarian Neuroscience Society. doi: 10.3389/conf.neuro.01.2009.04.047 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: 27 Feb 2009; Published Online: 27 Feb 2009. * Correspondence: András Birinyi, Department of Anatomy, University of Debrecen, Debrecen, Hungary, andras@chondron.anat.dote.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 András Birinyi Ildiko Weber Gabor Veres Miklos Antal Google András Birinyi Ildiko Weber Gabor Veres Miklos Antal Google Scholar András Birinyi Ildiko Weber Gabor Veres Miklos Antal PubMed András Birinyi Ildiko Weber Gabor Veres Miklos Antal 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.