DOCSLIB.ORG

Neurophysiological Characterisation of Neurons in the Rostral Nucleus Reuniens in Health and Disease

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Neurophysiological Characterisation of Neurons in the Rostral Nucleus Reuniens in Health and Disease Neurophysiological characterisation of neurons in the rostral nucleus reuniens in health and disease. Submitted by Darren Walsh, to the University of Exeter as a thesis for the degree of Doctor of Philosophy in Medical Studies, September 2017. This thesis is available for Library use on the understanding that it is copyright material and that no quotation from the thesis may be published without proper acknowledgement. I certify that all material in this thesis which is not my own work has been identified and that no material has previously been submitted and approved for the award of a degree by this or any other University. (Signature) ……………………………………………………………………………… Word Count = 44,836 1 Abstract Evidence is mounting for a role of the nucleus reuniens (Re) in higher cognitive function. Despite growing interest, very little is known about the intrinsic neurophysiological properties of Re neurons and, to date, no studies have examined if alterations to Re neurons may contribute to cognitive deficits associated with normal aging or dementia. Work presented chapter 3 provides the first detailed description of the intrinsic electrophysiological properties of rostral Re neurons in young adult (~5 months) C57- Bl/6J mice. This includes a number of findings which are highly atypical for thalamic relay neurons including tonic firing in the theta frequency at rest, a paucity of hyperpolarisation-activated cyclic nucleotide–gated (HCN) mediated currents, and a diversity of responses observed in response to depolarising current injections. Additionally this chapter includes a description of a novel form of intrinsic plasticity which alters the functional output of Re neurons. Chapter 4 investigates whether the intrinsic properties of Re neurons are altered in aged (~15 month) C57-Bl/6J mice as compared to a younger control group (~5 months). The intrinsic properties were remarkably similar across age ranges suggesting that alterations to the intrinsic properties of Re neurons do not contribute to age-related cognitive deficits. Chapter 5 investigates whether alterations to the intrinsic properties of Re neurons occur in the J20 model of amyloidopathy. Alterations to the resting membrane potential (RMP), propensity to rebound fire, and a reduction in action potential (AP) width were observed. This suggests that alterations to the intrinsic properties of Re neurons may contribute to cognitive deficits observed in Alzheimer’s disease (AD). Chapter 6 investigates whether alterations to the intrinsic properties of Re neurons occur in a mouse model (CHMP2Bintron5) of frontotemporal dementia (FTD). Only subtle changes were observed suggesting that alterations to the intrinsic properties of Re neurons does not contribute to cognitive deficits observed in FTD linked to chromosome 3 (FTD-3). 2 Acknowledgements First and foremost, I would like to thank my supervisors Prof. Andy Randall and Dr. Jon Brown for all their help and support over the last 4 years. Needless to say without their input none of this would have been possible. I would also like to thank all of the Hatherly crew, past and present, for their warmth, friendship and making this Irish country bumpkin feel at home in the metropolis that is Devon. Particular thanks go to Hannah Smithers (who prepared some of the slices used in chapter 3) and Tom Ridler, who have been there all the way. To quote Drizzy Drake, “Started from the bottom now we’re here”. Next a special thanks goes to the Fabreeze Brothers (Ben H, Myles J, Tom H, and Jeff L) for the stimulating quasi-intellectual pub talk, both scientific and otherwise, and for not losing faith when I wandered. To Soraya, for believing in me when I didn’t and your unwavering ability to make me smile, I am more grateful than you could ever know. Finally to my family at home. I did this for you guys. I hope ye are proud. This work is dedicated to the memory of my late grandfather Tommy Kelly. A victim of Alzheimer’s disease; I couldn’t have done it without him. 3 Table of Contents Abstract ..................................................................................................................... 2 Acknowledgements .................................................................................................. 3 List of figures ........................................................................................................... 7 List of tables ............................................................................................................. 9 Abbreviations ........................................................................................................... 9 1 Introduction ....................................................................................................... 12 1.1 General electrophysiological properties of neurons. ................................... 12 1.1.1 Resting membrane potential. ................................................................ 12 1.1.2 Passive membrane properties .............................................................. 14 1.1.3 Voltage-gated ion channels. ................................................................. 15 1.1.4 The neuronal action potential. .............................................................. 16 1.1.5 Synaptic transmission. .......................................................................... 18 1.1.6 Neuronal oscillations ............................................................................ 20 1.2 The thalamus .............................................................................................. 21 1.2.1 Neuroanatomy of the thalamus. ............................................................ 21 1.2.2 First and higher order relays influence on cortical function. .................. 22 1.2.3 Intrinsic electrophysiological properties of thalamic relay neurons ....... 24 1.3 The nucleus reuniens. ................................................................................. 27 1.3.1 Connectivity of the nucleus reuniens. ................................................... 28 1.3.2 The role of the nucleus reuniens in hippocampal prefrontal interactions 29 1.3.3 Cellular diversity in the nucleus reuniens.............................................. 32 1.3.4 The effect of experimental manipulation of the nucleus reuniens on cognitive function. ............................................................................................. 32 1.3.5 The role of the nucleus reuniens in disease. ........................................ 35 1.4 The effects of physiological aging on the brain. .......................................... 37 1.4.1 Regional decline in brain volume with physiological aging ................... 38 1.4.2 Changes in intrinsic excitability with physiological aging ...................... 38 1.5 Major Neurocognitive Disorders. ................................................................. 39 1.5.1 Alzheimer’s Disease. ............................................................................ 39 1.5.2 Frontotemporal Dementia. .................................................................... 43 1.5.3 Mouse models of dementia. .................................................................. 44 1.6 Aims ............................................................................................................ 46 2 Materials and Methods ...................................................................................... 52 4 2.1 Ethical approval and animals ...................................................................... 52 2.2 Slice preparation ......................................................................................... 52 2.3 Visual identification of neurons in the rostral nucleus reuniens ................... 53 2.4 Electrophysiological recordings ................................................................... 54 2.4.1 Whole cell patch clamp ......................................................................... 54 2.5 Data analysis ............................................................................................... 60 2.6 Staining for amyloid plaques ....................................................................... 64 3 Intrinsic electrophysiological properties of neurons of the rostral nucleus reuniens ................................................................................................................... 60 3.1 Introduction ................................................................................................. 60 3.2 Methods ...................................................................................................... 61 3.3 Results ........................................................................................................ 62 3.3.1 Cellular properties at in the absence of injected current ....................... 62 3.3.2 Spontaneous synaptic input .................................................................. 68 3.3.3 Passive and active membrane properties ............................................. 72 3.3.4 Apparent absence of HCN like current ................................................. 76 3.3.5 Afterpotential following elicitation of a single spike. .............................. 83 3.3.6 Action potential production in response to αEPSC current injections. .. 84 3.3.7 Firing behaviour in response to square current potentials are voltage dependant ......................................................................................................... 88 3.3.8 Electrophysiological and
Load more

Recommended publications
  • Behavioral and Electrophysiological Properties of Nucleus Reuniens: Role in Arousal, Spatial Navigation and Cognitive Processes
    BEHAVIORAL AND ELECTROPHYSIOLOGICAL PROPERTIES OF NUCLEUS REUNIENS: ROLE IN AROUSAL, SPATIAL NAVIGATION AND COGNITIVE PROCESSES by Tatiana Danela Viena A Dissertation Submitted to the Faculty of Charles E. Schmidt College of Science In Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy Florida Atlantic University Boca Raton, FL December 2018 Copyright 2018 by Tatiana Danela Viena ii ACKNOWLEDGEMENTS First, I wish to express my sincere thanks to my advisor Dr. Robert P. Vertes for the opportunity to work on these experiments and for his guidance and patience in completing this project. I also would like to thank the members of my committee, Dr. Robert W. Stackman and Dr. Timothy A. Allen for their challenging questions and suggestions regarding this project, but more importantly for their support. In addition, I want to thank Dr. Stephanie Linley for patiently teaching, guiding and empowering me whenever it was needed. I am grateful to all of the undergraduate research assistants who volunteered their time to assist in the many aspects of this project. They are too many to be named here, but you know who you are! I also would like to extend my gratitude to all of the wonderful individuals who one way or another assisted me over my graduate years and the many programs that sponsored my research activities. I also want to give a special recognition to my family (Bernardo, Randee and Elysse) for their unconditional love and support; and my mother and her daily words of encouragement. Thanks for always believing in me and pushing me to get to the finish line.
    [Show full text]
  • Nucleus Reuniens Thalami Modulates Activity in Hippocampal Field CA1 Through Excitatory and Inhibitory Mechanisms
    The Journal of Neuroscience, July 15, 1997, 17(14):5640–5650 Nucleus Reuniens Thalami Modulates Activity in Hippocampal Field CA1 through Excitatory and Inhibitory Mechanisms M. J. Dolleman-Van der Weel,1,2 F. H. Lopes da Silva,2 and M. P. Witter1 1Graduate School for Neurosciences Amsterdam, Research Institute for Neurosciences, Faculty of Medicine, Department of Anatomy and Embryology, Vrije Universiteit, 1081 BT Amsterdam, The Netherlands, and 2Institute of Neurobiology, Faculty of Biology, University of Amsterdam, 1098 SM Amsterdam, The Netherlands The nucleus reuniens thalami (RE) originates dense projections extracellularly recorded units in strata oriens/alveus and distal to CA1, forming asymmetrical synapses on spines (50%) and radiatum, indicative of the activation of local interneurons. dendrites (50%). The hypothesis that RE input modulates trans- Thus, RE seems to modulate transmission in CA1 through a mission in CA1 through excitation of both pyramidal cells and (subthreshold) depolarization of pyramidal cells and a supra- interneurons was tested using electrophysiological methods in threshold excitation of putative inhibitory oriens/alveus and the anesthetized rat. The RE–CA1 afferents were selectively radiatum interneurons. stimulated at their origin; evoked field potentials and unit ac- RE-evoked monosynaptic or disynaptic field potentials were tivity were recorded in CA1. RE-evoked depth profiles showed associated with stimulation of rostral or caudal RE, respectively. a prominent negative deflection in the stratum lacunosum- Anatomically, a projection from caudal to rostral RE was dem- moleculare and a positive one in the stratum radiatum. The onstrated that can account for the disynaptic RE–CA1 input. lacunosum-moleculare sink–radiatum source configuration is Because caudal RE receives input from the hippocampus via compatible with RE-elicited depolarization of apical dendrites the subiculum, we propose the existence of a closed RE– of pyramidal cells.
    [Show full text]
  • Basic Organization of Projections from the Oval and Fusiform Nuclei of the Bed Nuclei of the Stria Terminalis in Adult Rat Brain
    THE JOURNAL OF COMPARATIVE NEUROLOGY 436:430–455 (2001) Basic Organization of Projections From the Oval and Fusiform Nuclei of the Bed Nuclei of the Stria Terminalis in Adult Rat Brain HONG-WEI DONG,1,2 GORICA D. PETROVICH,3 ALAN G. WATTS,1 AND LARRY W. SWANSON1* 1Neuroscience Program and Department of Biological Sciences, University of Southern California, Los Angeles, California 90089-2520 2Institute of Neuroscience, The Fourth Military Medical University, Xi’an, Shannxi 710032, China 3Department of Psychology, Johns Hopkins University, Baltimore, Maryland 21218 ABSTRACT The organization of axonal projections from the oval and fusiform nuclei of the bed nuclei of the stria terminalis (BST) was characterized with the Phaseolus vulgaris-leucoagglutinin (PHAL) anterograde tracing method in adult male rats. Within the BST, the oval nucleus (BSTov) projects very densely to the fusiform nucleus (BSTfu) and also innervates the caudal anterolateral area, anterodorsal area, rhomboid nucleus, and subcommissural zone. Outside the BST, its heaviest inputs are to the caudal substantia innominata and adjacent central amygdalar nucleus, retrorubral area, and lateral parabrachial nucleus. It generates moderate inputs to the caudal nucleus accumbens, parasubthalamic nucleus, and medial and ventrolateral divisions of the periaqueductal gray, and it sends a light input to the anterior parvicellular part of the hypothalamic paraventricular nucleus and nucleus of the solitary tract. The BSTfu displays a much more complex projection pattern. Within the BST, it densely innervates the anterodorsal area, dorsomedial nucleus, and caudal anterolateral area, and it moderately innervates the BSTov, subcommissural zone, and rhomboid nucleus. Outside the BST, the BSTfu provides dense inputs to the nucleus accumbens, caudal substantia innominata and central amygdalar nucleus, thalamic paraventricular nucleus, hypothalamic paraventricular and periventricular nuclei, hypothalamic dorsomedial nucleus, perifornical lateral hypothalamic area, and lateral tegmental nucleus.
    [Show full text]
  • The Ventral Midline Thalamus (Reuniens and Rhomboid Nuclei) Contributes to the Persistence of Spatial Memory in Rats
    The Journal of Neuroscience, July 18, 2012 • 32(29):9947–9959 • 9947 Behavioral/Systems/Cognitive The Ventral Midline Thalamus (Reuniens and Rhomboid Nuclei) Contributes to the Persistence of Spatial Memory in Rats Michae¨l Loureiro, Thibault Cholvin, Joe¨lle Lopez, Nicolas Merienne, Asma Latreche, Brigitte Cosquer, Karine Geiger, Christian Kelche, Jean-Christophe Cassel,* and Anne Pereira de Vasconcelos* Laboratoire d’Imagerie et de Neurosciences Cognitives, UMR 7237 Centre National de la Recherche Scientifique (CNRS), Universite´ de Strasbourg, Institut Fe´de´ratif de Recherche 37 de Neurosciences, GDR 2905 du CNRS, Faculte´ de Psychologie, F-67000 Strasbourg, France The formation of enduring declarative-like memories engages a dialog between the hippocampus and the prefrontal cortex (PFC). Electrophysiological and neuroanatomical evidence for reciprocal connections with both of these structures makes the reuniens and rhomboid nuclei (ReRh) of the thalamus a major functional link between the PFC and hippocampus. Using immediate early gene imaging (c-Fos), fiber-sparing excitotoxic lesion, and reversible inactivation in rats, we provide evidence demonstrating a contribution of the ReRh to the persistence of a spatial memory. Intact rats trained in a Morris water maze showed increased c-Fos expression (vs home cage and visible platform groups: Ͼ500%) in the ReRh when tested in a probe trial at a 25 d delay, against no change ata5ddelay; behavioral performance was comparable at both delays. In rats subjected to excitotoxic fiber-sparing NMDA lesions circumscribed to the ReRh, we found normal acquisition of the water-maze task (vs sham-operated controls) and normal probe trial performance at the 5 d delay, but there was no evidence for memory retrieval at the 25 d delay.
    [Show full text]
  • Nucleus Reuniens Is Required for Encoding and Retrieving Precise Contextual Fear Memories in Rats
    bioRxiv preprint doi: https://doi.org/10.1101/340190; this version posted June 7, 2018. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under aCC-BY-NC-ND 4.0 International license. Nucleus reuniens is required for encoding and retrieving precise contextual fear memories in rats Karthik R. Ramanathan, Jingji Jin, Reed L. Ressler, and Stephen Maren Department of Psychological and Brain Sciences and Institute for Neuroscience, Texas A&M University, College Station, TX 77843, USA Corresponding author: Stephen Maren Department of Psychological and Brain Sciences TAMU 4235 Texas A&M University College Station, TX 77843-4235 [email protected] Running title: Nucleus reuniens and memory precision Conflict of Interest: The authors declare no competing financial interests. Acknowledgements: This work was supported by grants from the McKnight Endowment for Neuroscience (McKnight Memory and Cognitive Disorders Award to SM) and the National Institutes of Health (R01MH065961) to SM. The authors would like to thank Kelsey J. Clement for his technical assistance. Author contributions: KR and SM designed the experiments, analyzed the data and wrote the manuscript. KR, JJ and RR collected the data. Data availability: The datasets generated during and/or analyzed during the current study are available from the corresponding author upon request. 1 bioRxiv preprint doi: https://doi.org/10.1101/340190; this version posted June 7, 2018. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity.
    [Show full text]
  • Analysis of Evoked Activity Patterns of Human Thalamic Ventrolateral Neurons During Verbally Ordered Voluntary Movements
    Neuroscience Vol. 88, No. 2, pp. 377–392, 1998 Copyright 1998 IBRO. Published by Elsevier Science Ltd Printed in Great Britain. All rights reserved Pergamon PII: S0306-4522(98)00230-9 0306–4522/99 $19.00+0.00 ANALYSIS OF EVOKED ACTIVITY PATTERNS OF HUMAN THALAMIC VENTROLATERAL NEURONS DURING VERBALLY ORDERED VOLUNTARY MOVEMENTS S. RAEVA,* N. VAINBERG, YU. TIKHONOV and I. TSETLIN Laboratory of Human Cell Neurophysiology, Institute of Chemical Physics, Russian Academy of Sciences, 4 Kosygin Street, Moscow 117377, Russia and Burdenko Neurosurgery Institute, Russian Academy of Medical Sciences, Moscow, Russia Abstract––In the human thalamic ventralis lateralis nucleus the responses of 184 single units to verbally ordered voluntary movements and some somatosensory stimulations were studied by microelectrode recording technique during 38 stereotactic operations on parkinsonian patients. The tests were carried out on the same previously examined population of neurons classified into two groups, named A- and B-types according to the functional criteria of their intrinsic structure of spontaneous activity patterns. The evaluation of the responses of these units during functionally different phases of a voluntary movement (preparation, initiation, execution, after-effect) by means of the principal component analysis and correlation techniques confirmed the functional differences between A- and B-types of neurons and their polyvalent convergent nature. Four main conclusions emerge from the studies. (1) The differences of the patterns of A- and B-unit
    [Show full text]
  • The Anterior Thalamic Nuclei and Nucleus Reuniens: So Similar but So Different
    Neuroscience and Biobehavioral Reviews 119 (2020) 268–280 Contents lists available at ScienceDirect Neuroscience and Biobehavioral Reviews journal homepage: www.elsevier.com/locate/neubiorev Review article The anterior thalamic nuclei and nucleus reuniens: So similar but so different Mathias L. Mathiasen a, Shane M. O’Mara b, John P. Aggleton a,* a School of Psychology, Cardiff University, 70 Park Place, Cardiff, CF10 3AT, Wales, UK b School of Psychology and Institute of Neuroscience, Trinity College, Dublin, Ireland ARTICLE INFO ABSTRACT Keywords: Two thalamic sites are of especial significance for understanding hippocampal – diencephalic interactions: the Cingulate cortex anterior thalamic nuclei and nucleus reuniens. Both nuclei have dense, direct interconnections with the hip­ Hippocampus pocampal formation, and both are directly connected with many of the same cortical and subcortical areas. These Mammillary bodies two thalamic sites also contain neurons responsive to spatial stimuli while lesions within these two same areas Memory can disrupt spatial learning tasks that are hippocampal dependent. Despite these many similarities, closer Prefrontal cortex Retrosplenial cortex analysis reveals important differences in the details of their connectivity and the behavioural impact of lesions in Spatial memory these two thalamic sites. These nuclei play qualitatively different roles that largely reflectthe contrasting relative Subiculum importance of their medial frontal cortex interactions (nucleus reuniens) compared with their retrosplenial, Thalamus cingulate, and mammillary body interactions (anterior thalamic nuclei). While the anterior thalamic nuclei are critical for multiple aspects of hippocampal spatial encoding and performance, nucleus reuniens contributes, as required, to aid cognitive control and help select correct from competing memories. 1. Introduction in encoding and retrieving multiple aspects of space and navigation.
    [Show full text]
  • The Network Organization of Rat Intrathalamic Macroconnections and a Comparison with Other Forebrain Divisions
    The network organization of rat intrathalamic macroconnections and a comparison with other forebrain divisions Larry W. Swansona,1, Olaf Spornsb,c, and Joel D. Hahna aDepartment of Biological Sciences, University of Southern California, Los Angeles, CA 90089; bIndiana University Network Science Institute, Indiana University, Bloomington, IN 47405; and cDepartment of Psychological and Brain Sciences, Indiana University, Bloomington, IN 47405 Contributed by Larry W. Swanson, May 17, 2019 (sent for review April 8, 2019; reviewed by Zhanyan Fu and Leah A. Krubitzer) The thalamus is 1 of 4 major divisions of the forebrain and is of cortical regions (6). In contrast, the THe (habenular nuclei) and usually subdivided into epithalamus, dorsal thalamus, and ventral THv (reticular and ventral lateral geniculate nuclei, intergeniculate thalamus. The 39 gray matter regions comprising the large dorsal leaflet, zona incerta, and fields of Forel) are much smaller and thalamus project topographically to the cerebral cortex, whereas have virtually no projections to the cerebral cortex (6). the much smaller epithalamus (2 regions) and ventral thalamus (5 For the purposes of this analysis, axonal connections among all regions) characteristically project subcortically. Before analyzing 46 thalamic nuclei recognized on one side of the rat brain in a extrinsic inputs and outputs of the thalamus, here, the intrinsic standard atlas (7) have been considered (whether THe, THd, or connections among all 46 gray matter regions of the rat thalamus THv) along with the connections established by these nuclei with on each side of the brain were expertly collated and subjected to the 46 corresponding thalamic nuclei on the other side of the network analysis.
    [Show full text]
  • Thalamus.Pdf
    Thalamus 583 THALAMUS This lecture will focus on the thalamus, a subdivision of the diencephalon. The diencephalon can be divided into four areas, which are interposed between the brain stem and cerebral hemispheres. The four subdivisions include the hypothalamus to be discussed in a separate lecture, the ventral thalamus containing the subthalamic nucleus already discussed, the epithalamus which is made up mostly of the pineal body, and the dorsal thalamus (henceforth referred to as the thalamus) which is the focus of this lecture. Although we will not spend any time in lecture on the pineal body, part of the epithalamus, it does have some interesting features as well as some clinical relevance. The pineal is a small midline mass of glandular tissue that secretes the hormone melatonin. In lower mammals, melatonin plays a central role in control of diurnal rhythms (cycles in body states and hormone levels that follow the day- night cycle). In humans, at least a portion of the control of diurnal rhythms has been taken over by the hypothalamus, but there is increasing evidence that the pineal and melatonin play at least a limited role. Recent investigations have demonstrated a role for melatonin in sleep, tumor reduction and aging. Additionally, based on the observation that tumors of the pineal can induce a precocious puberty in males it has been suggested that the pineal is also involved in timing the onset of puberty. In many individuals the pineal is partially calcified and can serve as a marker for the midline of the brain on x- rays. Pathological processes can sometimes be detected by a shift in its position.
    [Show full text]
  • Diencephalon Diencephalon
    Diencephalon Diencephalon • Thalamus dorsal thalamus • Hypothalamus pituitary gland • Epithalamus habenular nucleus and commissure pineal gland • Subthalamus ventral thalamus subthalamic nucleus (STN) field of Forel Diencephalon dorsal surface Diencephalon ventral surface Diencephalon Medial Surface THALAMUS Function of the Thalamus • Sensory relay – ALL sensory information (except smell) • Motor integration – Input from cortex, cerebellum and basal ganglia • Arousal – Part of reticular activating system • Pain modulation – All nociceptive information • Memory & behavior – Lesions are disruptive Classification of Thalamic Nuclei I. Lateral Nuclear Group II. Medial Nuclear Group III. Anterior Nuclear Group IV. Posterior Nuclear Group V. Metathalamic Nuclear Group VI. Intralaminar Nuclear Group VII. Thalamic Reticular Nucleus Classification of Thalamic Nuclei LATERAL NUCLEAR GROUP Ventral Nuclear Group Ventral Posterior Nucleus (VP) ventral posterolateral nucleus (VPL) ventral posteromedial nucleus (VPM) Input to the Thalamus Sensory relay - Ventral posterior group all sensation from body and head, including pain Projections from the Thalamus Sensory relay Ventral posterior group all sensation from body and head, including pain LATERAL NUCLEAR GROUP Ventral Lateral Nucleus Ventral Anterior Nucleus Input to the Thalamus Motor control and integration Projections from the Thalamus Motor control and integration LATERAL NUCLEAR GROUP Prefrontal SMA MI, PM SI Ventral Nuclear Group SNr TTT GPi Cbll ML, STT Lateral Dorsal Nuclear Group Lateral
    [Show full text]
  • Studies on Ti&Diencephalon of the Vir'i' 4Nia Opossum
    STUDIES ON TI&DIENCEPHALON OF THE VIR'I' 4NIA OPOSSUM PART 11. THE FIB,,RiC70NNECTIONS IN NORMAL AND EXPP MENTAL MATERIAL' LAVID BODIAN National Research Coq :,'gFeJlow in Medicine, Laboratory of Comparative N6dro1ogyl Depart3 ,# of Anatomy, The University of Michigan, Ann Arbo., and the Department of Anatomy, Thq,gniueraity of Chicago, Illinois THIBTI-'*.INPLATES (TWENTY-SIX FIGURES) CONTENTS Introduction ..... .............................................. 208 Material and methods.. .................. ..................... 209 Internal capsule and tha. mie radiations ................................ 210 Dorsal thalamic eommisswes and internal medullary lamina. .............. 213 Supraoptic decussations ................................................ 215 Connections of the dorsal thalamus.. ................................... 223 Anterior nuclear group. ............... ........... 223 Medial nuclear group ............................................. 224 Midline and commissural nuclei. ... ............... 227 Lateral nuclear group ............................................. 230 Ventral nuclear group and medial lemniscus.. ........................ 231 Geniculate nuelel and associated optic and auditory nuclei of the di- mesencephal I: junction. Tecto-reuniens fiber systems. ............ 233 The optic tracts and nucleus opticus tegmenti.. ...................... 237 Conriections of the ventral thalamus. ....... ............... 239 Zona incerta .................................................. Nucleus genic! +us lateralis ventralis.
    [Show full text]
  • Projections of the Paraventricular and Paratenial Nuclei of the Dorsal Midline Thalamus in the Rat
    THE JOURNAL OF COMPARATIVE NEUROLOGY 508:212–237 (2008) Projections of the Paraventricular and Paratenial Nuclei of the Dorsal Midline Thalamus in the Rat ROBERT P. VERTES* AND WALTER B. HOOVER Center for Complex Systems and Brain Sciences, Florida Atlantic University, Boca Raton, Florida 33431 ABSTRACT The paraventricular (PV) and paratenial (PT) nuclei are prominent cell groups of the midline thalamus. To our knowledge, only a single early report has examined PV projections and no previous study has comprehensively analyzed PT projections. By using the antero- grade anatomical tracer, Phaseolus vulgaris leucoagglutinin, and the retrograde tracer, FluoroGold, we examined the efferent projections of PV and PT. We showed that the output of PV is virtually directed to a discrete set of limbic forebrain structures, including ‘limbic’ regions of the cortex. These include the infralimbic, prelimbic, dorsal agranular insular, and entorhinal cortices, the ventral subiculum of the hippocampus, dorsal tenia tecta, claustrum, lateral septum, dorsal striatum, nucleus accumbens (core and shell), olfactory tubercle, bed nucleus of stria terminalis (BST), medial, central, cortical, and basal nuclei of amygdala, and the suprachiasmatic, arcuate, and dorsomedial nuclei of the hypothalamus. The posterior PV distributes more heavily than the anterior PV to the dorsal striatum and to the central and basal nuclei of amygdala. PT projections significantly overlap with those of PV, with some important differences. PT distributes less heavily than PV to BST and to the amygdala, but much more densely to the medial prefrontal and entorhinal cortices and to the ventral subiculum of hippocampus. As described herein, PV/PT receive a vast array of afferents from the brainstem, hypothalamus, and limbic forebrain, related to arousal and attentive states of the animal, and would appear to channel that information to structures of the limbic forebrain in the selection of appropriate responses to changing environmental conditions.
    [Show full text]