DOCSLIB.ORG

Role of Microglia in Ataxias

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Role of Microglia in Ataxias Review Role of Microglia in Ataxias Austin Ferro 1, Carrie Sheeler 1, Juao-Guilherme Rosa 1 and Marija Cvetanovic 1,2 1 - Department of Neuroscience, University of Minnesota, Minneapolis, MN 55455, USA 2 - Institute for Translational Neuroscience, University of Minnesota, Minneapolis, MN 55455, USA Correspondence to Austin Ferro: [email protected], [email protected], [email protected], [email protected] https://doi.org/10.1016/j.jmb.2019.01.016 Edited by Kristine Karla Freude Abstract Microglia, the resident macrophages of the central nervous system, critically influence neural function during development and in adulthood. Microglia are also profoundly sensitive to insults to the brain to which they respond with process of activation that includes spectrum of changes in morphology, function, and gene expression. Ataxias are a class of neurodegenerative diseases characterized by motor discoordination and predominant cerebellar involvement. In case of inherited forms of ataxia, mutant proteins are expressed throughout the brain and it is unclear why cerebellum is particularly vulnerable. Recent studies demonstrated that cerebellar microglia have a uniquely hyper-vigilant immune phenotype compared to microglia from other brain regions. These findings may indicate that microglia actively contribute to cerebellar vulnerability in ataxias. Here we review current knowledge about cerebellar microglia, their activation, and their role in the pathogenesis of ataxias. In addition, we briefly review advantages and disadvantages of several experimental approaches available to study microglia. © 2019 Published by Elsevier Ltd. Introduction bulbar muscular atrophy, and dentatorubral and pallidoluysian atrophy [2,7]. The clinical manifesta- The ataxias are a family of neurological disorders tion of polyQ ataxias is very similar and often characterized by loss of balance and coordinated includes progressive cerebellar ataxia, oculomotor motor function [1]. Ataxias are classified as hered- abnormalities, dysarthria (difficulties in speech), itary, sporadic, or acquired to denote what is known pigmentary retinopathy, peripheral neuropathy, and of their etiology. Hereditary ataxias are caused by a cognitive dysfunction [8]. Disruption of cerebellar wide range of known genetic mutations with varying cortical function accounts for many of the motor and patterns of inheritance [2]. Sporadic ataxias have an cognitive symptoms in polyQ ataxias [9]. The only unknown cause with potential environmental and sources of output from the cerebellar cortex to deep genetic components [2]. Acquired ataxias, on the cerebellar nuclei are axonal projections from Pur- other hand, include disorders with endogenous or kinje cells. Cerebellar afferents modulate cerebellar exogenous causes that are not genetic in nature, cortical output via transmission to Purkinje cell such as those arising from focal cerebellar damage somas (climbing fibers) and to granule cells (mossy caused by toxic agents, vitamin deficiencies, im- fibers) whose parallel fibers synapse onto the mune reactions, infection, and injury [3–5]. dendritic arbors of several Purkinje cells. PolyQ Autosomal dominant cerebellar ataxias caused by ataxias are characterized by the predominant the expansion of CAG trinucleotide repeats, includ- neurodegeneration of cerebellar afferents and the ing spinocerebellar ataxia (SCA) types 1, 2, 3, 6, 7, Purkinje cells, thereby disrupting the circuitry and and 17, are among the most understood ataxias function of the cerebellar cortex [10]. [1,6]. As CAG encodes for glutamine, these ataxias Animal models of several CAG repeat diseases have belong to the group of polyglutamine (polyQ) been generated, providing insight into the mechanisms diseases that includes Huntington's disease, spinal underlying polyQ-induced degeneration of Purkinje 0022-2836/© 2019 Published by Elsevier Ltd. Journal of Molecular Biology (2019) 431, 1792–1804 Review: Role of Microglia in Ataxias 1793 neurons [9,11–16]. However, the contribution of non- a relatively long developmental time. Human cerebellar neuronal cells, including microglia, astrocytes, and development extends from the early embryonic period oligodendrocytes to the pathology of ataxia has been until the first postnatal years [28]. This protracted period much less explored. of postnatal development leaves the cerebellum Microglia have emerged as key players in age- and vulnerable to extrinsic and intrinsic injury [29,30]. disease-associated neurodegeneration, contributing to Early injury may alter the roles of microglia in cerebellar tissue support and disease progression [17]. Indeed, development, causing developmental abnormalities microglia have been shown to contribute to neurode- that can have far reaching effects in adulthood. For generation through cell autonomous and cell non- example, during early postnatal cerebellar develop- autonomous mechanisms [18–20]. These studies ment [postnatal day 3 (P3)] in mice, normal apoptosis of provide evidence that microglia may play active roles Purkinje neurons was strongly reduced by selective in diseases traditionally thought to be predominantly elimination of microglia, indicating that microglia neuronal. Here, we will review the importance of eliminate superfluous Purkinje neurons [23].AtP6–7, microglia in the cerebellum and the evidence for and microglia promote GABA-ergic inhibition on Purkinje against their contribution to the pathogenesis of the cells and prune superfluous synapses [31]. Elimination ataxias and their effect on other non-neuronal cells. of immature, functionally redundant synapses during Furthermore, we will also review novel techniques that postnatal development is essential for the formation of show promise in overcoming current limitations of the functional cerebellar network [32]. Disruption of studying microglia, namely, the use of human-induced these developmental processes can lead to cerebellar pluripotent stem cells (hiPSCs). dysfunction [33,34]. Importantly, studies on mouse models of SCA1 have demonstrated that disruption of these processes may also pre-dispose the cerebellum Uniqueness of Cerebellar Microglia to age-induced neurodegeneration [35,36]. To maintain adult brain homeostasis, microglia Microglia are the resident macrophages of the central constantly extend and retract their processes to survey nervous system and have a wide variety of functions the local environment for synaptic activity [37], patho- during development as well as in adulthood. Microglia gen presence, and injury [38,39]. Madry et al. [40] surveille the local neural state and aid in maintenance recently established that constant microglial surveil- of the extracellular space. Moreover, functions that lance depends on the expression of the two-pore microglia perform are dependent on age, inflammatory domain potassium (K+) channel (THIK1). They dem- state, and location. Unlike other brain cells, microglia onstrated that tonic THIK1 activity maintains microglial originate from the erythromyeloid progenitors that in membrane potential and that blocking THIK1 reduces mice develop around embryonic day 8.5 (E8.5) in the microglial ramification and surveillance. These results yolk sack. Erythromyeloid progenitors migrate to the implicate a potential role of extracellular K+ concentra- brain starting around E9.5 and continue to do so until tion, arising from local neuronal activity, as a control the blood–brain barrier is formed around E14 [21,22]. mechanism for microglial surveillance. While it is During the early development, microglia have lasting unclear whether physiological changes in extracellular effects on the developing neural architecture, including K+ concentration are sufficiently large to alter microglial their well-understood role in superfluous cellular and surveillance, pathological changes in neuronal or synaptic pruning [23,24]. Recent studies using astroglial function are likely to do so. For example, it genome-wide chromatin and gene expression profiling is possible that enhanced neuronal activity [41] and/or demonstrated that microglia undergo three distinct reduced clearance by astrocytes [42] may increase developmental stages: early microglia (until E14), pre- extracellular K+, thereby altering microglial surveillance microglia (from E14 to a few weeks after birth), and and morphology through THIK1. adult microglia (from a few weeks after birth). These Microglia do seem to be attracted to areas of high developmental steps are regulated by distinct tran- physiological neuronal activity, whether drawn by scriptional factors that allow for different roles of THIK1signalingtoareasofincreased extracellular K+ microglia at each of these stages of life [25,26]. [40] or by adenosine signaling through the purinergic Importantly, sensome genes, through which microglia receptor P2Y12 [38,43].Liet al. [37] demonstrated that sense the environment [27],areexpressedeveninthe microglia briefly (~5 min) contact highly active neurons, early stages of development. This indicates that subsequently reducing their activity. Intriguingly, during microglia are environmentally alert at all stages of ischemic injury, the duration of these microglia–neuron development and may respond to brain insults. contacts is prolonged (~1 h) and can lead to synapse Moreover, evidence suggests that exposure to insults removal [41]. Furthermore, Davalos et al. [38] demon- during development may alter the developmental roles strated that increase in ATP causes rapid recruitment of of microglia and thus
Load more

Recommended publications
  • Molecular Plasticity of Adult Bergmann Fibers Is Associated with Radial Migration of Grafted Purkinje Cells
    The Journal of Neuroscience, January 1994, 14(i): 124-133 Molecular Plasticity of Adult Bergmann Fibers Is Associated with Radial Migration of Grafted Purkinje Cells Constantino Sotelo,’ Rosa-Magda Alvarado-Mallart,i Monique Frain,2 and Muriel Verner ‘Neuromorphologie: Dkveloppement, Evolution, INSERM U. 106, HBpital de la Salpktrikre, 75651 Paris Cedex 13, France, *Biologic Molkulaire du Dkveloppement, INSERM U. 368 Ecole Normale Supkrieure, 75230 Paris Cedex, France, and 31nstitut Cochin de Gbnbtique Molkulaire, CJF 9003 INSERM, 75014 Paris, France Embryonic Purkinje cells (PCs) from cerebellar primordia adult cerebellum and become functionally integrated into the grafted in adult pcd mutant cerebellum replace missing PCs synaptic circuitry of the cerebellarcortex of the host (Sotelo and of the host, and become synaptically integrated into the de- Alvarado-Mallart, 1991). The cerebellar mutant mouse strains fective cerebellar circuit. This process of neuronal replace- .LJC~,nr, and Lc, in which Purkinje cells (PCs) die (Sidman and ment starts with the invasion of grafted PCs into the host Green, 1970; Mullen et al., 1976; Caddy and Biscoe, 1979; cerebellum, and their radial migration through its molecular Wassef et al., 1987; Dumesnil-Bousez and Sotelo, 1992), have layer. The present study is aimed at determining whether provided models for studying graft integration (Sotelo and Al- the glial axes for this migration are embryonic radial glial varado-Mallart, 1986, 1987a, 1991, 1992; Dumesnil-Bousezand cells that comigrate with the grafted PCs, or adult Bergmann Sotelo, 1993). Penetration of grafted PCs into the cerebellum fibers of the host, transiently reexpressing the molecular of mutant hosts begins 3-4 d after grafting (DAG 3-4) by tan- cues needed for their guidance of the migration.
    [Show full text]
  • Cerebellar Granule Cells in Culture
    Proc. Nati. Acad. Sci. USA Vol. 83, pp. 4957-4961, July 1986 Neurobiology Cerebellar granule cells in culture: Monosynaptic connections with Purkinje cells and ionic currents (excitatory postsynaptic potential/patch-clamp) ToMoo HIRANO, YOSHIHIRo KUBO, AND MICHAEL M. WU Department of Neurobiology, Institute of Brain Research, School of Medicine, University of Tokyo, Tokyo, Japan Communicated by S. Hagiwara, March 6, 1986 ABSTRACT Electrophysiological properties of cerebellar tissue was dissociated by triturating with a fire-polished granule cells and synapses between granule and Purkinje cells Pasteur pipette in Ca-free Hanks' balanced salt solution were studied in dissociated cultures. Electrophysiological prop- containing 0.05% DNase and 12 mM MgSO4. The cells were erties of neurons and synapses in the mammalian central centrifuged at 150 x g at 40C and the pelleted cells were nervous system are best studied in dissociated cell cultures resuspended at a concentration of about 106 cells per ml in a because of good target cell visibility, control over the contents defined medium (9). One milliliter ofthe cell suspension from of the extracellular solution, and the feasibility of whole-cell newborn rats was plated first in a Petri dish (3.5 cm in patch electrode recording, which has been a powerful tech- diameter) containing several pieces ofheat-sterilized, poly(L- nique in analyzing biophysical properties of ionic channels in lysine)-coated coverslips, and then 1 ml of fetal cell suspen- small cells. We have applied this whole-cell recording technique sion was added. One-half of the culture medium was ex- to cultured cerebellar granule cells whose electrophysiological changed with fresh medium once a week.
    [Show full text]
  • Profound Functional and Molecular Diversity of Mitochondria Revealed by Cell Type-Specific Profiling in Vivo
    bioRxiv preprint doi: https://doi.org/10.1101/403774; this version posted August 29, 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. Profound functional and molecular diversity of mitochondria revealed by cell type-specific profiling in vivo Authors: Caroline Fecher1,2,3,#, Laura Trovò1,2,#, Stephan A. Müller2,4, Nicolas Snaidero1,2, Jennifer Wettmarshausen5,6, Sylvia Heink7, Oskar Ortiz8,$, Ingrid Wagner9, Ralf Kühn8,$$, Jana Hartmann10, Rosa Maria Karl10, Arthur Konnerth10,11,12, Thomas Korn7,11, Wolfgang Wurst2,8,11,13, Doron Merkler9, Stefan F. Lichtenthaler2,4,11, Fabiana Perocchi5,6,11 and Thomas Misgeld1,2,11,12,* Affiliations: 1 Institute of Neuronal Cell Biology, Technical University of Munich, Germany 2 German Center for Neurodegenerative Diseases, Munich, Germany 3 Graduate School of Systemic Neuroscience, Ludwig-Maximilians University, Munich, Germany 4 Neuroproteomics, School of Medicine, Klinikum rechts der Isar, and Institute for Advanced Study, Technical University of Munich, Germany 5 Gene Center Munich, Ludwig-Maximilians University, Munich, Germany 6 Institute for Diabetes and Obesity, Helmholtz Zentrum München, Munich, Germany 7 Experimental Neuroimmunology, Klinikum rechts der Isar, Technical University of Munich, Germany 8 Institute of Developmental Genetics, Helmholtz Zentrum München, Munich, Germany 9 Department of
    [Show full text]
  • Differences in the Developmental Patterns of Three Microtubule-Associated Proteins in the Rat Cerebellum’
    0270.8474/85/0504-0977$02.00/O The Journal of Neuroscience Copyright 0 Society for Neuroscience Vol. 5, No. 4, pp. 977-991 Printed in U.S.A. April 1985 Differences in the Developmental Patterns of Three Microtubule-associated Proteins in the Rat Cerebellum’ ROBERT BERNHARDT,2 GERDA HUBER,3 AND ANDREW MATUS Friedrich Miescher-lnstitut, P. 0. Box 2543, CH-4002 Base/, Switzerland Abstract MAPS are potentially important physiological regulators of neuronal differentiation. The developmental distribution patternS of microtubule- It has become clear that microtubules of different tissues and cell associated proteins (MAPS) 1, 2, and 3 were studied using types are characterized by different MAPS. Thus, a category of high three monoclonal antibodies. lmmunochemical staining at the molecular weight MAPS, later identified as MAP2, is exclusively light and electron microscopic levels demonstrated the spe- expressed in adult neurons where it is most concentrated in den- cific localization of each MAP in different cellular and sub- drites (Matus et al., 1981, 1983; Caceres et al., 1983, 1984; Wiche cellular compartments. (i) MAPS, which is specifically asso- et al., 1983; Bernhardt and Matus, 1984; De Camilli et al., 1984). ciated with dendritic microtubules in the adult brain, is strictly This suggested the possibility that MAP2 could be specifically associated with growing dendrites from the onset of their involved in the formation of dendritic microtubules and hence could formation. (ii) MAP3, a recently described MAP of M, = play a significant role in the regulation of dendrite growth. This idea 180,000, which in the adult brain is associated with neurofi- found further support from immunohistochemical data of developing lament-rich axons and glial processes, is associated with brain (Bernhardt and Matus, 1982; Matus et al., 1983; Burgoyne and axons from the beginning of outgrowth.
    [Show full text]
  • Lnteractions Between Cerebellar Purkinje Cells and Their Associated
    Neuron-glia interactions of Purkinje cells is preserved in organotypic cerebellar astrocytes that is reflected in some neuron-glia cultures. As defined by Palay and Chan-Palay (1974), interactions that are not necessarily typical, but may be the sheaths are formed predominantly by processes of characteristic of more tightly coupled cells. With this Golgi epithelial cells, the astrocytes that give rise to the caveat in mind, we will examine the evidence for these radial Bergmann fibers that extend through the particular astrocytic properties. molecular layer of the cerebellar cortex and provide a lattice for granule cell migration (Rakic, 1971). These The cerebellar culture models astrocytes are often, though inappropriately, referred to as "Bergmann glia." Purkinje cells are the only neurons Parasagittally oriented cerebellar explants derived in the cerebellar cortex that are fully ensheathed by from newborn (within 24 hours after birth) Swiss- astrocytes, whereas basket and stellate cells have only Webster mice and maintained in Maximow chambers for partial sheaths and Golgi and granule cells (Fig. 3) are 2 or more weeks exhibit many of the structural and generally unensheathed (Palay and Chan-Palay, 1974). It functional characteristics of the cerebellum in vivo (Seil, is this close relationship between Purkinje cells and 1972; Leiman and Seil, 1973; reviewed in Seil, 1979, Fig. 1. Purkinje cell from an untreated control cerebellar culture, 15 DIV. Shown is the soma and a pottion of a dendrite (d) extending upward. The soma is surrounded by an astrocytic sheath, which appears as a relatively clear area immediately adjacent to the smoothly contoured soma membrane. Five axon terminals intenupt the sheath to contact the soma, two of which are synaptic contacts (large arrows).
    [Show full text]
  • Cerebellar Histology & Circuitry
    Cerebellar Histology & Circuitry Histology > Neurological System > Neurological System CEREBELLAR HISTOLOGY & CIRCUITRY SUMMARY OVERVIEW Gross Anatomy • The folding of the cerebellum into lobes, lobules, and folia allows it to assume a tightly packed, inconspicuous appearance in the posterior fossa. • The cerebellum has a vast surface area, however, and when stretched, it has a rostrocaudal expanse of roughly 120 centimeters, which allows it to hold an estimated one hundred billion granule cells — more cells than exist within the entire cerebral cortex. - It is presumed that the cerebellum's extraordinary cell count plays an important role in the remarkable rehabilitation commonly observed in cerebellar stroke. Histology Two main classes of cerebellar nuclei • Cerebellar cortical neurons • Deep cerebellar nuclei CEREBELLAR CORTICAL CELL LAYERS Internal to external: Subcortical white matter Granule layer (highly cellular) • Contains granule cells, Golgi cells, and unipolar brush cells. Purkinje layer 1 / 9 • Single layer of large Purkinje cell bodies. • Purkinje cells project a fine axon through the granule cell layer. - Purkinje cells possess a large dendritic system that arborizes (branches) extensively and a single fine axon. Molecular layer • Primarily comprises cell processes but also contains stellate and basket cells. DEEP CEREBELLAR NUCLEI From medial to lateral: Fastigial Globose Emboliform Dentate The globose and emboliform nuclei are also known as the interposed nuclei • A classic acronym for the lateral to medial organization of the deep nuclei is "Don't Eat Greasy Food," for dentate, emboliform, globose, and fastigial. NEURONS/FUNCTIONAL MODULES • Fastigial nucleus plays a role in the vestibulo- and spinocerebellum. • Interposed nuclei are part of the spinocerebellum. • Dentate nucleus is part of the pontocerebellum.
    [Show full text]
  • Clusters of Cerebellar Purkinje Cells Control Their Afferent Climbing Fiber
    Clusters of cerebellar Purkinje cells control their afferent climbing fiber discharge Joseph Chaumonta, Nicolas Guyonb, Antoine M. Valeraa, Guillaume P. Duguéb, Daniela Popab, Paikan Marcaggib, Vanessa Gautheronc, Sophie Reibel-Foissetd, Stéphane Dieudonnéb, Aline Stephane, Michel Barrota, Jean-Christophe Casself, Jean-Luc Duponta, Frédéric Doussaua, Bernard Poulaina, Fekrije Selimic,1, Clément Lénab,1, and Philippe Isopea,1,2 aInstitut des Neurosciences Cellulaires et Intégratives, Centre National de la Recherche Scientifique, Unité Propre de Recherche 3212, Université de Strasbourg, 67084 Strasbourg, France; bInstitut de Biologie de l’Ecole Normale Supérieure, Centre National de la Recherche Scientifique, Unité Mixte de Recherche 8197, Institut National de la Santé et de la Recherche Médicale, Unité 1024, 75005 Paris, France; cCenter for Interdisciplinary Research in Biology, Collège de France, Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7241, Institut National de la Santé et de la Recherche Médicale, Unité 1050, 75005 Paris, France; dChronobiotron, Unité Mixte de Service 3415, Centre National pour la Recherche Scientifique, Université de Strasbourg, 67084 Strasbourg, France; eInstitut de Génétique Moléculaire et Cellulaire, Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7104, Institut National de la Santé et de la Recherche Médicale, Unité 964, Université de Strasbourg, 67400 Illkirch, France; and fLaboratoire de Neurosciences Cognitives et Adaptatives, Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7364, Université de Strasbourg, 67084 Strasbourg, France Edited by Shigetada Nakanishi, Osaka Bioscience Institute, Suita, Japan, and approved August 29, 2013 (received for review February 5, 2013) Climbing fibers, the projections from the inferior olive to the These results indicate that PCs may tonically modulate the cerebellar cortex, carry sensorimotor error and clock signals that nucleo-olivary pathway.
    [Show full text]
  • Monoclonal Antibodies to Specific Astroglial and Neuronal Antigens Reveal the Cytoarchitecture of the Bergmann Glia Fibers in the Cerebellum’
    0270.6474/84/0401-0265$02.00/O The Journal of Neuroscience Copyright 0 Society for Neuroscience Vol. 4, No. 1, pp. 265-273 Printed in U.S.A. January 1984 MONOCLONAL ANTIBODIES TO SPECIFIC ASTROGLIAL AND NEURONAL ANTIGENS REVEAL THE CYTOARCHITECTURE OF THE BERGMANN GLIA FIBERS IN THE CEREBELLUM’ ANGEL L. DE BLAS Department of Neurobiology and Behavior, State University of New York at Stony Brook, Stony Brook, New York 11794 Received May 11, 1983; Revised August 22, 1983; Accepted August 22, 1983 Abstract The cytoarchitecture of the cerebellar Bergmann fibers in the adult rat was investigated. Two monoclonal antibodies, one specific for the Bergmann fibers and astrocyte processes and the other specific for the cell bodies and dendrites of the Purkinje cells as well as an antiserum to the glial fibrillary acidic protein, were used in immunocytochemical peroxidase-antiperoxidase assays. The Bergmann fibers are revealed as columns organized in long vertical palisades parallel to the longitudinal plane of the folium. The palisades are not continuous; instead they are formed by sets of two to six aligned Bergmann fibers. Each of these sets of Bergmann fibers is separated from its longitudinally aligned neighbors by gaps. Each Bergmann fiber is formed by a bundle of two to four Bergmann glia processes which frequently show a helical organization. These results help to reconcile the different views on the organization of the .Bergmann fibers derived from the’studies done with the light microscope versus those done with the electron microscope. The Bergmann glia may play a fundamental role in directing the geometrical organi- zation of the cerebellar constituents.
    [Show full text]
  • Diversity Among Purkinje Cells in the Monkey Cerebellum (Deep Cerebellar Nucle!/Monoclonal Antibody/Immunohstochemlstry) VERNON M
    Proc. Nati. Acad. Sci. USA Vol. 82, pp. 7131-7135, October 1985 Neurobiology Diversity among Purkinje cells in the monkey cerebellum (deep cerebellar nucle!/monoclonal antibody/immunohstochemlstry) VERNON M. INGRAM*, MARILEE P. OGRENt, CLARE L. CHATOT*, JAMIE M. GOSSELS*, AND BARBARA BLANCHARD OWENS* Departments of *Biology and tPsychology and Brain Science, Massachusetts Institute of Technology, Cambridge, MA 02139 Communicated by Walle J. H. Nauta, June 24, 1985 ABSTRACT A monoclonal antibody (Bi) produced Monkey cerebellum is not as well studied as the rodent against rat embryonic forebrain membranes shows specific and cerebellum. Sagittal microzones of motilin-containing striking immunohistochemical staining of Purkinje cells in the Purkinje cells in the vermis have been reported (1), but monkey cerebellum in a pattern of broad parasagittal alter- GABA-containing Purkinje cells do not show a banded nating bands of cells either possessing or lacking the Bi pattern in the monkey. Most other histochemical or immuno- antigen. In addition, the neurons of the deep cerebellar nuclei cytochemical investigations of zones or bands among the and some neurons of the motor cortex and of the spinal cord Purkinje cells have been carried out in other mammals. It also contain the Bi antigen. Neurons with the Bi antigen were remains to be seen which observations made in other mam- also seen in the somatosensory cortex, the vestibular and mals will apply to the monkey. Functional parasagittal cochlear nuclei, and the retina. microzones, defined as sets of Purkinje cells that project to a distinct group oftarget neurons, have been described for the Although the Purkinje cells of the mammalian cerebellum monkey flocculus (14) and may also exist in other parts ofthe appear remarkably homogeneous with Nissl stains, immu- cerebellar cortex of the monkey.
    [Show full text]
  • Cell Counting in the Human Brain: Traditional and Electronic Methods*
    Postgrad Med J: first published as 10.1136/pgmj.51.600.722 on 1 October 1975. Downloaded from Postgraduate Medical Journal (October 1975) 51, 722-726. Cell counting in the human brain: traditional and electronic methods* J. A. N. CORSELLIS R. L. ALSTON F.R.C.P., F.R.C.Path., F.R.C.Psych. F.I.M.L.T. A. K. H. MILLER A.M.I.EE. Department of Neuropathology, Runwell Hospital, Wickford, Essex Summary brain. Indeed, Delisle Burns epitomized this view in Whether or not a proportion of nerve cells disappears 1955 when he calculated that 100,000 nerve cells die from the human brain during adult life remains a every day in the life of an adult man. Such an controversial question 80 years after it was first asked. hypothesis has its attractions, particularly for the In this paper the authors review briefly the reasons for young. It looks moreover as if it could well be true this uncertainty and describe an attempt to find an since the loss of nervous tissue and of cortical nerve answer in so far as the cerebellar Purkinje cells are cells is often striking in the brains of organically concerned. A loss of about 2-5 % per decade was demented old people. It is then only a small step to identified. The problems raised by cell counting in the argue that such a pathological state is merely the cerebral cortex are outlined and a new method is extreme of what is liable to happen in varying described which may prove suitable for neuronal degrees to the population in general.
    [Show full text]
  • Calcium Signaling in Specialized Glial Cells
    GLIA 54:650–655 (2006) Calcium Signaling in Specialized Glial Cells MONICA R. METEA AND ERIC A. NEWMAN* Department of Neuroscience, University of Minnesota, Minneapolis, Minnesota KEY WORDS signaling in Muller€ cells is believed to play an essential glia; calcium; Muller€ cell; Bergmann glia; radial glia role in these intercellular interactions. 1 ABSTRACT Spontaneous and Evoked Ca2 Signaling This article reviews calcium signaling in three specialized in Muller€ Cells types of glial cells: Muller€ cells of the retina, Bergmann glial cells of the cerebellum, and radial glial cells of the developing Muller€ cells of the mammalian retina generate transient cortex. Muller€ cells generate spontaneous and neuronal activ- increases in Ca21 in the absence of evoked neuronal activ- 21 € ity-evoked increases in Ca .NeurontoMuller cell signaling ity (Newman, 2005). They occur at a frequency of 4.6 tran- is mediated by neuronal release of ATP and activation of glial sients per cell per 1,000 s. The transients range from 2.5 to P2Y receptors. Muller€ cells, in turn, modulate neuronal excit- 6 s in duration and are similar to those observed in astro- ability and mediate vasomotor responses. Bergmann glial cells also generate spontaneous and activity-evoked Ca21 cytes in brain slices (Nett et al., 2002; Parri et al., 2001) increases. Neuron to Bergmann glia signaling is mediated by and in vivo (Hirase et al., 2004). neuronal release of nitric oxide, noradrenaline, and gluta- The retina offers an important advantage over brain 1 mate.InBergmannglia,Ca21 increases control the struc- slice preparations in studies of Ca2 signaling in that tural and functional interactions between these cells and Ca21 increases in Muller€ cells can be induced by a natural Purkinje cell synapses.
    [Show full text]
  • Golgi Cell Dendrites Are Restricted by Purkinje Cell Stripe Boundaries in the Adult Mouse Cerebellar Cortex
    2820 • The Journal of Neuroscience, March 12, 2008 • 28(11):2820–2826 Cellular/Molecular Golgi Cell Dendrites Are Restricted by Purkinje Cell Stripe Boundaries in the Adult Mouse Cerebellar Cortex Roy V. Sillitoe,1 Seung-Hyuk Chung,1 Jean-Marc Fritschy,2 Monica Hoy,1 and Richard Hawkes1 1Department of Cell Biology and Anatomy, Genes and Development Research Group, and Hotchkiss Brain Institute, Faculty of Medicine, The University of Calgary, Calgary, Alberta, Canada T2N 4N1, and 2Institute of Pharmacology and Toxicology, University of Zurich, CH-8057 Zurich, Switzerland Despite the general uniformity in cellular composition of the adult cerebellar cortex, there is a complex underlying pattern of parasagittal stripes of Purkinje cells with characteristic molecular phenotypes and patterns of connectivity. It is not known whether interneuron processes are restricted at stripe boundaries. To begin to address the issue, three strategies were used to explore how cerebellar Golgi cell dendrites are organized with respect to parasagittal stripes: first, double immunofluorescence staining combining anti-neurogranin to identify Golgi cell dendrites with the Purkinje cell compartmentation antigens zebrin II/aldolase C, HNK-1, and phospholipase C␤4; second, zebrin II immunohistochemistry combined with a rapid Golgi–Cox impregnation procedure to reveal Golgi cell dendritic arbors; third, stripe antigen expression was used on sections of a GlyT2-EGFP transgenic mouse in which reporter expression is prominent in Golgi cell dendrites. In each case, the dendritic projections of Golgi cells were studied in the vicinity of Purkinje cell stripe boundaries. The data presented here show that the dendrites of a cerebellar interneuron, the Golgi cell, respect the fundamental cerebellar stripe cytoarchitecture.
    [Show full text]