DOCSLIB.ORG

Retinotopic Responses in the Visual Cortex Elicited by Epiretinal Electrical Stimulation in Normal and Retinal Degenerate Rats

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text

Load more

https://doi.org/10.1167/tvst.7.5.33 Article Retinotopic Responses in the Visual Cortex Elicited by Epiretinal Electrical Stimulation in Normal and Retinal Degenerate Rats Kiran Nimmagadda1,2 and James D. Weiland3,4 1 Neuroscience Graduate Program, University of Southern California, Los Angeles, CA, USA 2 USC – Caltech MD/PhD Program, Los Angeles, CA, USA 3 Department of Biomedical Engineering, The University of Michigan, Ann Arbor, MI, USA 4 Department of Ophthalmology and Visual Sciences, The University of Michigan, Ann Arbor, MI, USA Correspondence: James D. Weiland, Purpose: Electronic retinal prostheses restore vision in people with outer retinal The University of Michigan, Bio- degeneration by electrically stimulating the inner retina. We characterized visual medical Engineering and Ophthal- cortex electrophysiologic response elicited by electrical stimulation of retina in mology, 2200 Bonisteel Blvd, 1107 normally sighted and retinal degenerate rats. Carl A. Gerstacker Building, Ann Methods: Nine normally sighted Long Evans and 11 S334ter line 3 retinal degenerate Arbor, MI 48109, USA. e-mail: (rd) rats were used to map cortical responses elicited by epiretinal electrical [email protected] stimulation in four quadrants of the retina. Six normal and six rd rats were used to Received: 12 February 2018 compare the dendritic spine density of neurons in the visual cortex. Accepted: 24 August 2018 Results: The rd rats required higher stimulus amplitudes to elicit responses in the Published: 31 October 2018 visual cortex. The cortical electrically evoked responses (EERs) for both healthy and rd rats show a dose-response characteristic with respect to the stimulus amplitude. The Keywords: electrical stimulation; EER maps in healthy rats show retinotopic organization. For rd rats, cortical retinotopy cortical electrophysiology; retino- is not well preserved. The neurons in the visual cortex of rd rats show a 10% higher topy;rat;retinitispigmentosa dendritic spine density than in the healthy rats. Citation: Nimmagadda K, Weiland Conclusions: Cortical activity maps, produced when epiretinal stimulation is applied JD. Retinotopic responses in the to quadrants of the retina, exhibit retinotopy in normal but not rd rats. This is likely visual cortex elicited by epiretinal due to a combination of degeneration of the retina and increased stimulus thresholds electrical stimulation in normal and in rd, which broadens the activated area of the retina. retinal degenerate rats. Trans Vis Sci Tech. 2018;7(5):33, https://doi.org/ Translational Relevance: Loss of retinotopy is evident in rd rats. If a similar loss of retinotopy is present in humans, retinal prostheses design must include flexibility to 10.1167/tvst.7.5.33 account for patient specific variability. Copyright 2018 The Authors RP is more severe and both are characterized by Introduction progressive loss of photoreceptors. The photoreceptor loss in AMD and RP can lead to complete blindness The two most common outer retinal degenerative and profound disability. It is estimated that approx- diseases are age-related macular degeneration (AMD) and retinitis pigmentosa (RP). RP is a general term imately 15 million people suffer from vision loss due for a disparate group of inherited diseases with over to these diseases worldwide, and these numbers are 200 genetic mutations that have been identified so far. expected to rise as the population ages. The etiology of AMD is multifactorial1,2 and includes The societal impact of outer retinal degenerative genetic mutations in photoreceptors and accumula- disorders is tremendous. These disorders are one of tion of drusen. Age, smoking, race (more common the leading causes of adult-onset blindness. Studies among Caucasians than among African-Americans or from multiple countries3,4 of patients with AMD has Hispanics/Latinos), and family history are the main shown that the disease has a significant emotional and risk factors for AMD. AMD is more prevalent, but functional impact on patients, providers, and society 1 TVST j 2018 j Vol. 7 j No. 5 j Article 33 This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License. Downloaded from tvst.arvojournals.org on 09/27/2021 Nimmagadda and Weiland overall. In the United States, there are approximately and electrical stimulus applied subretinally in nor- 700,000 new AMD patients each year,5,6 10% of who mally sighted rats.17 In this paper, we characterize will become legally blind. As the United States electrophysiologic response in the visual cortex of population ages, it is estimated7 that more elderly healthy Long Evans rats and retinal degenerate (rd) persons will become blind from AMD than from S334ter line 3 rats elicited by electrical stimulation of glaucoma and diabetic retinopathy combined. A the retina. Electrophysiology recording using micro- value-based analysis8 of the societal burden of electrodes in the visual cortex provides a functional AMD estimates the yearly cost of the disease borne readout in the visual system of the effect of electrically by the United States economy to be $30 billion. stimulating the retina. The human (and rat) visual Because these studies are restricted to AMD, they cortex has an orderly arrangement of visual field underestimate the societal impact of the full spectrum processing, termed retinotopy. This retinotopic orga- of outer retinal degenerative diseases. While RP has a nization represents specificity in the spatial organiza- lower incidence than AMD, affecting approximately tion of connections in the various layers of the visual one in 2000 individuals worldwide,9 the individual system with respect to the visual field, and is an impact is more devastating and costlier due to the important element of functional vision. Maintenance earlier onset and greater severity of RP compared of retinotopy after photoreceptor loss is unclear. One with AMD. of the overarching goals in the development of retinal There is currently no known cure for vision loss prostheses is to provide functional vision for patients caused by outer retinal degeneration. Postmortem suffering from photoreceptor degeneration. Because histologic analysis of retinal tissue in RP and AMD retinotopy is a fundamental aspect of functional patients has given us valuable insight. Even when vision, our research aims to investigate the nature of photoreceptor cell loss is virtually complete, other cortical retinotopy elicited by the electrical stimula- cells in the retina generally survive,10 enough to be tion of the retina in normally sighted and blind rats. activated11 by electrical stimulus. This finding pro- This paper presents the first work in the study of vided the impetus for using implantable electronic visual cortex retinotopy in response to epiretinal retinal prostheses to provide functional vision for electrical stimulation of the healthy versus rd retina. patients with blindness due to photoreceptor degen- While the anatomic changes in the retina in response eration. Photoreceptor degeneration has been to photoreceptor degeneration are well studied, the shown12 to lead to extensive remodeling in the inner effect on visual cortex neurons has not been studied as retina. Electronic retinal prostheses electrically stim- extensively. We present preliminary comparison of ulate surviving neurons and circuitry in the inner anatomic differences in the visual cortex neurons retina and represent an emerging technology13 in the between normally sighted and blind rats using the treatment of such diseases. Golgi stain and comparing spine density. There has been limited previous research in characterizing in vivo visual cortex electrophysiology Materials and Methods response elicited by epiretinal electrical stimulation of retina. Published results have been limited to exper- Animals iments performed on three anesthetized cats that primarily investigated safety and surgical technique14 Healthy Long Evans (postnatal day P90–P120, n ¼ of stimulating electrode array implantation. Two 9) rats and S334ter line 3 rats with retinal degener- studies have compared cortical responses elicited by ation (rd) (P120–P300, n ¼ 11) were used for cortical photovoltaic subretinal prostheses with visual-evoked response mapping of electrical stimulation of retina in potentials15,16 in normally sighted and blind rats. four quadrants of the retina. The weight of the rd rats More recently, intrinsic optical imaging was used to ranged from 228 to 278 g (mean 256 g with standard study the visual cortex response elicited by light deviation of 21.1 g). The weight of the rd rats ranged stimulus versus electrical stimulus applied to subret- from 270 to 321 g (mean 298 g with standard inal electrode arrays in normally sighted rats.17 deviation of 19.3 g). The retinal degenerate rats were Rat models of retinal degeneration have greatly bred in the USC animal care facilities by mating improved the understanding of the pathophysiology17 homozygous S334ter line 3 rats with Long Evans rats of photoreceptor degenerative diseases. Rats have (Envigo, Hayward, CA). The homozygous S334ter also been used to characterize retinotopic maps of the line 3 rats for breeding were obtained from the Rat visual cortex activity18 in response to light stimulus Resource Research Center of the University of 2 TVST j 2018 j Vol. 7 j No. 5 j Article 33 Downloaded from tvst.arvojournals.org on 09/27/2021 Nimmagadda and Weiland Missouri. Because the mutation is dominant, all positioned midway within the
Recommended publications
  • Biophysically Realistic Neuron Models for Simulation of Cortical Stimulation

    Biophysically Realistic Neuron Models for Simulation of Cortical Stimulation

    bioRxiv preprint doi: https://doi.org/10.1101/328534; this version posted August 20, 2018. The copyright holder for this preprint (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. 1 Biophysically Realistic Neuron Models for Simulation of Cortical Stimulation Authors: Aman S. Aberra1, Angel V. Peterchev1,2,3,4, Warren M. Grill1,3,4,5,* 1 Dept. of Biomedical Engineering, School of Engineering, Duke University, NC 2 Dept. of Psychiatry and Behavioral Sciences, School of Medicine, Duke University, NC 3 Dept. of Electrical and Computer Engineering, School of Engineering, Duke University, NC 4 Dept. of Neurosurgery, School of Medicine, Duke University, NC 5 Dept. of Neurobiology, School of Medicine, Duke University, NC * Corresponding Author: Warren M. Grill Keywords: neuron model, cortex, myelination, simulation, electric field, stimulation, axon bioRxiv preprint doi: https://doi.org/10.1101/328534; this version posted August 20, 2018. The copyright holder for this preprint (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. 2 1. Abstract Objective. We implemented computational models of human and rat cortical neurons for simulating the neural response to cortical stimulation with electromagnetic fields. Approach. We adapted model neurons from the library of Blue Brain models to reflect biophysical and geometric properties of both adult rat and human cortical neurons and coupled the model neurons to exogenous electric fields (E-fields). The models included 3D reconstructed axonal and dendritic arbors, experimentally-validated electrophysiological behaviors, and multiple, morphological variants within cell types.
  • Imaging Retinotopic Maps in the Human Brain ⇑ Brian A

    Imaging Retinotopic Maps in the Human Brain ⇑ Brian A

    Vision Research 51 (2011) 718–737 Contents lists available at ScienceDirect Vision Research journal homepage: www.elsevier.com/locate/visres Review Imaging retinotopic maps in the human brain ⇑ Brian A. Wandell , Jonathan Winawer Psychology Department, Stanford University, Stanford, CA 94305, United States article info abstract Article history: A quarter-century ago visual neuroscientists had little information about the number and organization of Received 5 April 2010 retinotopic maps in human visual cortex. The advent of functional magnetic resonance imaging (MRI), a Received in revised form 2 August 2010 non-invasive, spatially-resolved technique for measuring brain activity, provided a wealth of data about Available online 6 August 2010 human retinotopic maps. Just as there are differences amongst non-human primate maps, the human maps have their own unique properties. Many human maps can be measured reliably in individual sub- Keywords: jects during experimental sessions lasting less than an hour. The efficiency of the measurements and the Visual field maps relatively large amplitude of functional MRI signals in visual cortex make it possible to develop quanti- Retinotopy tative models of functional responses within specific maps in individual subjects. During this last quarter- Human visual cortex Functional specialization century, there has also been significant progress in measuring properties of the human brain at a range of Optic radiation length and time scales, including white matter pathways, macroscopic properties of gray and white mat- Visual field map clusters ter, and cellular and molecular tissue properties. We hope the next 25 years will see a great deal of work that aims to integrate these data by modeling the network of visual signals.
  • Contribution of Apical and Basal Dendrites of L2/3 Pyramidal Neurons to Orientation Encoding in Mouse V1 Jiyoung Park1,4*†, Athanasia Papoutsi3†, Ryan T

    Contribution of Apical and Basal Dendrites of L2/3 Pyramidal Neurons to Orientation Encoding in Mouse V1 Jiyoung Park1,4*†, Athanasia Papoutsi3†, Ryan T

    bioRxiv preprint doi: https://doi.org/10.1101/566588; this version posted March 5, 2019. 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. Contribution of Apical and Basal Dendrites of L2/3 Pyramidal Neurons to Orientation Encoding in Mouse V1 Jiyoung Park1,4*†, Athanasia Papoutsi3†, Ryan T. Ash2,4, Miguel A. Marin2, Panayiota Poirazi3* & Stelios M. Smirnakis4* 1Program in Structural and Computational Biology and Molecular Biophysics, Baylor College of Medicine, Houston, Texas 2Department of Neuroscience, Baylor College of Medicine, Houston, Texas 3Institute of Molecular Biology and Biotechnology (IMBB), Foundation of Research and Technology Hellas (FORTH), Vassilika Vouton, Heraklion, Crete, Greece 4Brigham and Women’s Hospital and Jamaica Plain VA Hospital, Harvard Medical School, Boston, MA †Equal contribution. * Correspondence: [email protected], [email protected], [email protected] Abstract: Pyramidal neurons integrate synaptic inputs from basal and apical dendrites to generate stimulus-specific responses. It has been proposed that feed-forward inputs to basal dendrites drive a neuron’s stimulus preference, while feedback inputs to apical dendrites sharpen selectivity. However, how a neuron’s dendritic domains relate to its functional selectivity has not been demonstrated experimentally. We performed 2-photon dendritic micro-dissection on layer- 2/3 pyramidal neurons in mouse primary visual cortex. We found that removing the apical dendritic tuft did not alter orientation-tuning. Furthermore, orientation-tuning curves were remarkably robust to the removal of basal dendrites: ablation of 2-3 basal dendrites was needed to cause a small shift in orientation preference, without significantly altering tuning width.
  • Interaction Among Ocularity, Retinotopy and On-Center/Off­ Center Pathways During Development

    Interaction Among Ocularity, Retinotopy and On-Center/Off­ Center Pathways During Development

    INTERACTION AMONG OCULARITY, RETINOTOPY AND ON-CENTER/OFF­ CENTER PATHWAYS DURING DEVELOPMENT Shigeru Tanaka Fundamental Research Laboratories, NEC Corporation, 34 Miyukigaoka, Tsukuba, Ibaraki 305, Japan ABSTRACT The development of projections from the retinas to the cortex is mathematically analyzed according to the previously proposed thermodynamic formulation of the self-organization of neural networks. Three types of submodality included in the visual afferent pathways are assumed in two models: model (A), in which the ocularity and retinotopy are considered separately, and model (B), in which on-center/off-center pathways are considered in addition to ocularity and retinotopy. Model (A) shows striped ocular dominance spatial patterns and, in ocular dominance histograms, reveals a dip in the binocular bin. Model (B) displays spatially modulated irregular patterns and shows single-peak behavior in the histograms. When we compare the simulated results with the observed results, it is evident that the ocular dominance spatial patterns and histograms for models (A) and (B) agree very closely with those seen in monkeys and cats. 1 INTRODUCTION A recent experimental study has revealed that spatial patterns of ocular dominance columns (ODes) observed by autoradiography and profiles of the ocular dominance histogram (ODH) obtained by electrophysiological experiments differ greatly between monkeys and cats. ODes for cats in the tangential section appear as beaded patterns with an irregularly fluctuating bandwidth (Anderson, Olavarria and Van Sluyters 1988); ODes for monkeys are likely to be straight parallel stripes (Hubel, Wiesel and LeVay, 1977). The typical ODH for cats has a single peak in the middle of the ocular dominance corresponding to balanced response in ocularity (Wiesel and Hubel, 1974).
  • Neuronal Organization of Olfactory Bulb Circuits

    Neuronal Organization of Olfactory Bulb Circuits

    REVIEW ARTICLE published: 03 September 2014 doi: 10.3389/fncir.2014.00098 Neuronal organization of olfactory bulb circuits Shin Nagayama 1*, Ryota Homma1 and Fumiaki Imamura 2 1 Department of Neurobiology and Anatomy, The University of Texas Medical School at Houston, Houston, TX, USA 2 Department of Pharmacology, Pennsylvania State University College of Medicine, Hershey, PA, USA Edited by: Olfactory sensory neurons extend their axons solely to the olfactory bulb, which is Benjamin R. Arenkiel, Baylor College dedicated to odor information processing.The olfactory bulb is divided into multiple layers, of Medicine, USA with different types of neurons found in each of the layers. Therefore, neurons in the Reviewed by: olfactory bulb have conventionally been categorized based on the layers in which their cell Kazushige Touhara, University of Tokyo, Japan bodies are found; namely, juxtaglomerular cells in the glomerular layer, tufted cells in the Veronica Egger, external plexiform layer, mitral cells in the mitral cell layer, and granule cells in the granule Ludwig-Maximilians-Universität, cell layer. More recently, numerous studies have revealed the heterogeneous nature of each Germany Kathleen Quast, Baylor College of of these cell types, allowing them to be further divided into subclasses based on differences Medicine, USA in morphological, molecular, and electrophysiological properties. In addition, technical *Correspondence: developments and advances have resulted in an increasing number of studies regarding Shin Nagayama, Department of cell types other than the conventionally categorized ones described above, including short- Neurobiology and Anatomy, The axon cells and adult-generated interneurons. Thus, the expanding diversity of cells in the University of Texas Medical School at Houston, 6431 Fannin Street, olfactory bulb is now being acknowledged.
  • Action Potentials in Basal and Oblique Dendrites of Rat Neocortical Pyramidal Neurons Srdjan D

    Action Potentials in Basal and Oblique Dendrites of Rat Neocortical Pyramidal Neurons Srdjan D

    Physiology in Press; published online on May 9, 2003 as 10.1113/jphysiol.2002.033746 J Physiol (2003), xxx.x, pp. 000–000 DOI: 10.1113/jphysiol.2002.033746 © The Physiological Society 2003 www.jphysiol.org Action potentials in basal and oblique dendrites of rat neocortical pyramidal neurons Srdjan D. Antic Department of Cellular and Molecular Physiology, and Department of Neurobiology, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520, USA Basal and oblique dendrites comprise ~2/3 of the total excitable membrane in the mammalian cerebral cortex, yet they have never been probed with glass electrodes, and therefore their electrical properties and overall impact on synaptic processing are unknown. In the present study, fast multi- site voltage-sensitive dye imaging combined with somatic recording was used to provide a detailed description of the membrane potential transients in basal and oblique dendrites of pyramidal neurons during single and trains of action potentials (APs). The optical method allowed simultaneous measurements from several dendrites in the visual field up to 200 mm from the soma, thus providing a unique report on how an AP invades the entire dendritic tree. In contrast to apical dendrites, basal and oblique branches: (1) impose very little amplitude and time course modulation on backpropagating APs; (2) are strongly invaded by the somatic spike even when somatic firing rates reach 40 Hz (activity-independent backpropagation); and (3) do not exhibit signs of a ‘calcium shoulder’ on the falling phase of the AP. A compartmental model incorporating AP peak latencies and half-widths obtained from the apical, oblique and basal dendrites indicates that the specific intracellular resistance (Ri) is less than 100 V cm.
  • Retinotopy Versus Face Selectivity in Macaque Visual Cortex

    Retinotopy Versus Face Selectivity in Macaque Visual Cortex

    Retinotopy versus Face Selectivity in Macaque Visual Cortex Reza Rajimehr1,2, Natalia Y. Bilenko1, Wim Vanduffel1,3, 1 and Roger B. H. Tootell Downloaded from http://mitprc.silverchair.com/jocn/article-pdf/26/12/2691/1782578/jocn_a_00672.pdf by MIT Libraries user on 17 May 2021 Abstract ■ Retinotopic organization is a ubiquitous property of lower- Distinct subregions within face-selective patches showed tier visual cortical areas in human and nonhuman primates. In either (1) a coarse retinotopic map of eccentricity and polar macaque visual cortex, the retinotopic maps extend to higher- angle, (2) a retinotopic bias to a specific location of visual order areas in the ventral visual pathway, including area TEO field, or (3) nonretinotopic selectivity. In general, regions in the inferior temporal (IT) cortex. Distinct regions within IT along the lateral convexity of IT cortex showed more overlap cortex are also selective to specific object categories such as between retinotopic maps and face selectivity, compared with faces. Here we tested the topographic relationship between regions within the STS. Thus, face patches in macaques can be retinotopic maps and face-selective patches in macaque visual subdivided into smaller patches with distinguishable retino- cortex using high-resolution fMRI and retinotopic face stimuli. topic properties. ■ INTRODUCTION has been recently challenged by the demonstration of small Visual cortical areas are typically defined on the basis of receptive fields in anterior IT cortex (DiCarlo & Maunsell, differences in histology (cytoarchitecture and myelo- 2003; Op De Beeck & Vogels, 2000). architecture), anatomical connections, functional proper- How do the retinotopic maps in IT cortex relate to ties, and retinotopic organization (Felleman & Van Essen, the functionally defined category-selective areas? Neuro- 1991).
  • Transient Hypoxemia Chronically Disrupts Maturation of Preterm Fetal Ovine Subplate Neuron Arborization and Activity

    Transient Hypoxemia Chronically Disrupts Maturation of Preterm Fetal Ovine Subplate Neuron Arborization and Activity

    11912 • The Journal of Neuroscience, December 6, 2017 • 37(49):11912–11929 Development/Plasticity/Repair Transient Hypoxemia Chronically Disrupts Maturation of Preterm Fetal Ovine Subplate Neuron Arborization and Activity XEvelyn McClendon,1 Daniel C. Shaver,1 Kiera Degener-O’Brien,1 Xi Gong,1 Thuan Nguyen,2 Anna Hoerder-Suabedissen,3 Zolta´n Molna´r,3 Claudia Mohr,4 XBen D. Richardson,4 David J. Rossi,4 and Stephen A. Back1,5 1Department of Pediatrics and 2Public Health and Preventive Medicine, Oregon Health & Science University, Portland, Oregon 97239, 3Department of Physiology, Anatomy, and Genetics, University of Oxford, Oxford, United Kingdom OX1 3QX, 4Department of Integrative Physiology and Neuroscience, College of Veterinary Medicine, Washington State University, Pullman, Washington 99164, and 5Department of Neurology, Oregon Health & Science University, Portland, Oregon 97239 Preterm infants are at risk for a broad spectrum of neurobehavioral disabilities associated with diffuse disturbances in cortical growth and development. During brain development, subplate neurons (SPNs) are a largely transient population that serves a critical role to establish functional cortical circuits. By dynamically integrating into developing cortical circuits, they assist in consolidation of intra- cortical and extracortical circuits. Although SPNs reside in close proximity to cerebral white matter, which is particularly vulnerable to oxidative stress, the susceptibility of SPNs remains controversial. We determined SPN responses to two common insults to the preterm brain: hypoxia-ischemia and hypoxia. We used a preterm fetal sheep model using both sexes that reproduces the spectrum of human cerebral injury and abnormal cortical growth. Unlike oligodendrocyte progenitors, SPNs displayed pronounced resistance to early or delayed cell death from hypoxia or hypoxia-ischemia.
  • Autism Spectrum Disorder Susceptibility Gene TAOK2 Affects

    Autism Spectrum Disorder Susceptibility Gene TAOK2 Affects

    ART ic LE s Autism spectrum disorder susceptibility gene TAOK2 affects basal dendrite formation in the neocortex Froylan Calderon de Anda1,2, Ana Lucia Rosario1,2, Omer Durak1–3, Tracy Tran2,4,5, Johannes Gräff1,2, Konstantinos Meletis1–3,5, Damien Rei1,2, Takahiro Soda1,2, Ram Madabhushi1,2, David D Ginty2,4, Alex L Kolodkin2,4 & Li-Huei Tsai1–3 How neurons develop their morphology is an important question in neurobiology. Here we describe a new pathway that specifically affects the formation of basal dendrites and axonal projections in cortical pyramidal neurons. We report that thousand-and-one- amino acid 2 kinase (TAOK2), also known as TAO2, is essential for dendrite morphogenesis. TAOK2 downregulation impairs basal dendrite formation in vivo without affecting apical dendrites. Moreover, TAOK2 interacts with Neuropilin 1 (Nrp1), a receptor protein that binds the secreted guidance cue Semaphorin 3A (Sema3A). TAOK2 overexpression restores dendrite formation in cultured cortical neurons from Nrp1Sema− mice, which express Nrp1 receptors incapable of binding Sema3A. TAOK2 overexpression also ameliorates the basal dendrite impairment resulting from Nrp1 downregulation in vivo. Finally, Sema3A and TAOK2 modulate the formation of basal dendrites through the activation of the c-Jun N-terminal kinase (JNK). These results delineate a pathway whereby Sema3A and Nrp1 transduce signals through TAOK2 and JNK to regulate basal dendrite development in cortical neurons. Pyramidal neurons are abundant in brain regions associated with through the activation of JNK11. TAOK2 is subjected to alternative complex cognitive functions, including the cortex, hippocampus and splicing to produce the TAOK2α (140 kDa) and TAOK2β (120 kDa) amygdala1.
  • Down-Regulation of Dendritic Spine and Glutamic Acid Decarboxylase 67 Expressions in the Reelin Haploinsufficient Heterozygous Reeler Mouse

    Down-Regulation of Dendritic Spine and Glutamic Acid Decarboxylase 67 Expressions in the Reelin Haploinsufficient Heterozygous Reeler Mouse

    Down-regulation of dendritic spine and glutamic acid decarboxylase 67 expressions in the reelin haploinsufficient heterozygous reeler mouse Wen Sheng Liu*, Christine Pesold*, Miguel A. Rodriguez*, Giovanni Carboni*, James Auta*, Pascal Lacor*, John Larson*, Brian G. Condie†, Alessandro Guidotti*, and Erminio Costa*‡ *Psychiatric Institute, Department of Psychiatry, College of Medicine, University of Illinois, Chicago, IL 60612; and †Institute of Molecular Medicine and Genetics, Departments of Medicine and Cellular Biology and Anatomy, Medical College of Georgia, Augusta, GA 30912 Contributed by Erminio Costa, December 22, 2000 Heterozygous reeler mice (HRM) haploinsufficient for reelin ex- heterozygote reeler mice (HRM) and in heterozygote GAD67 Ϸ press 50% of the brain reelin content of wild-type mice, but are knockout mice (HG67M) and compared them to their respective phenotypically different from both wild-type mice and homozy- wild-type background mice (WTM). In the present study, we gous reeler mice. They exhibit, (i) a down-regulation of glutamic have also quantified the number of neurons immunopositive for acid decarboxylase 67 (GAD67)-positive neurons in some but not reelin in the motor area of the frontoparietal cortex (FPC) of every cortical layer of frontoparietal cortex (FPC), (ii) an increase of HRM, as well as the total number of neurons immunopositive for neuronal packing density and a decrease of cortical thickness NeuN and the number of glial cells stained by Nissl (13) because of neuropil hypoplasia, (iii) a decrease of dendritic spine expressed in each of the six layers of this cortical area. In WTM, expression density on basal and apical dendritic branches of motor HRM, and HG67M, we have also quantified the laminar expres- FPC layer III pyramidal neurons, and (iv) a similar decrease in sion of GAD67-immunopositive neurons and the dendritic spine dendritic spines expressed on the basal dendrite branches of CA1 density expressed by pyramidal neurons of layer III FPC and of pyramidal neurons of the hippocampus.
  • Contribution of Apical and Basal Dendrites to Orientation Encoding in Mouse V1 L2/3 Pyramidal Neurons

    Contribution of Apical and Basal Dendrites to Orientation Encoding in Mouse V1 L2/3 Pyramidal Neurons

    ARTICLE https://doi.org/10.1038/s41467-019-13029-0 OPEN Contribution of apical and basal dendrites to orientation encoding in mouse V1 L2/3 pyramidal neurons Jiyoung Park1,2,7*, Athanasia Papoutsi3,7, Ryan T. Ash1,4,5, Miguel A. Marin4,6, Panayiota Poirazi 3,8*& Stelios M. Smirnakis1,8* 1234567890():,; Pyramidal neurons integrate synaptic inputs from basal and apical dendrites to generate stimulus-specific responses. It has been proposed that feed-forward inputs to basal dendrites drive a neuron’s stimulus preference, while feedback inputs to apical dendrites sharpen selectivity. However, how a neuron’s dendritic domains relate to its functional selectivity has not been demonstrated experimentally. We performed 2-photon dendritic micro-dissection on layer-2/3 pyramidal neurons in mouse primary visual cortex. We found that removing the apical dendritic tuft did not alter orientation-tuning. Furthermore, orientation-tuning curves were remarkably robust to the removal of basal dendrites: ablation of 2 basal dendrites was needed to cause a small shift in orientation preference, without significantly altering tuning width. Computational modeling corroborated our results and put limits on how orientation preferences among basal dendrites differ in order to reproduce the post-ablation data. In conclusion, neuronal orientation-tuning appears remarkably robust to loss of dendritic input. 1 Brigham and Women’s Hospital and Jamaica Plain VA Hospital, Harvard Medical School, Boston, MA, USA. 2 Program in Structural and Computational Biology and Molecular Biophysics, Baylor College of Medicine, Houston, TX, USA. 3 Institute of Molecular Biology and Biotechnology (IMBB), Foundation of Research and Technology Hellas (FORTH), Vassilika Vouton, HeraklionCrete, Greece.
  • Dendritic Size of Pyramidal Neurons Differs Among Mouse Cortical

    Dendritic Size of Pyramidal Neurons Differs Among Mouse Cortical

    Cerebral Cortex July 2006;16:990--1001 doi:10.1093/cercor/bhj041 Advance Access publication September 29, 2005 Dendritic Size of Pyramidal Neurons Differs Ruth Benavides-Piccione1,2, Farid Hamzei-Sichani2, Inmaculada Ballesteros-Ya´n˜ez1, Javier DeFelipe1 and Rafael Yuste1,2 among Mouse Cortical Regions 1Instituto Cajal, Madrid, Spain and 2HHMI, Department of Biological Sciences, Columbia University, New York, USA Downloaded from https://academic.oup.com/cercor/article-abstract/16/7/990/425668 by University of Massachusetts Medical School user on 19 February 2019 Neocortical circuits share anatomical and physiological similarities a series of basic circuit diagrams based on anatomical and among different species and cortical areas. Because of this, electrophysiological data (Douglas et al., 1989, 1995; Douglas a ‘canonical’ cortical microcircuit could form the functional unit and Martin, 1991, 1998, 2004). According to their hypothesis, of the neocortex and perform the same basic computation on the common transfer function that the neocortex performs on different types of inputs. However, variations in pyramidal cell inputs could be related to the amplification of the signal structure between different primate cortical areas exist, indicating (Douglas et al., 1989) or a ‘soft’ winner-take-all algorithm that different cortical areas could be built out of different neuronal (Douglas and Martin, 2004). These ideas agree with the re- cell types. In the present study, we have investigated the dendritic current excitation present in cortical tissue which could then architecture of 90 layer II/III pyramidal neurons located in different exert a top-down amplification and selection on thalamic inputs cortical regions along a rostrocaudal axis in the mouse neocortex, (Douglas et al., 1995).