1. Neuroscience
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An inhibitory corticostriatal pathway

  1. Crystal Rock
  2. Hector Zurita
  3. Charles Wilson
  4. Alfonso junior Apicella  Is a corresponding author
  1. University of Texas at San Antonio, United States
Research Article
  • Cited 37
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Cite this article as: eLife 2016;5:e15890 doi: 10.7554/eLife.15890

Abstract

Anatomical and physiological studies have led to the assumption that the dorsal striatum receives exclusively excitatory afferents from the cortex. Here we test the hypothesis that the dorsal striatum receives also GABAergic projections from the cortex. We addressed this fundamental question by taking advantage of optogenetics and directly examining the functional effects of cortical GABAergic inputs to spiny projection neurons (SPNs) of the mouse auditory and motor cortex. We found that the cortex, via corticostriatal somatostatin neurons (CS-SOM), has a direct inhibitory influence on the output of the striatum SPNs. Our results describe a corticostriatal long-range inhibitory circuit (CS-SOM inhibitory projections → striatal SPNs) underlying the control of spike timing/generation in SPNs and attributes a specific function to a genetically defined type of cortical interneuron in corticostriatal communication.

Article and author information

Author details

  1. Crystal Rock

    Department of Biology, Neurosciences Institute, University of Texas at San Antonio, San Antonio, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Hector Zurita

    Department of Biology, Neurosciences Institute, University of Texas at San Antonio, San Antonio, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Charles Wilson

    Department of Biology, Neurosciences Institute, University of Texas at San Antonio, San Antonio, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Alfonso junior Apicella

    Department of Biology, Neurosciences Institute, University of Texas at San Antonio, San Antonio, United States
    For correspondence
    alfonso.apicella@utsa.edu
    Competing interests
    The authors declare that no competing interests exist.

Ethics

Animal experimentation: Apicella IACUC protocol number: IS00000135All animal procedures were approved by the Institutional Animal Care and Use Committee at the University of Texas at San Antonio. Procedures followed animal welfare guidelines set by the National Institutes of Health. Mice used in this experiment were housed in a vivarium maintaining a 12 hour light/dark schedule and given ad libidum access to mouse chow and water.Mice were initially anesthetized with isoflurane (3%; 1 L/min O2 flow) in preparation for the stereotaxic injections.

Reviewing Editor

  1. Sacha B Nelson, Brandeis University, United States

Publication history

  1. Received: March 10, 2016
  2. Accepted: May 8, 2016
  3. Accepted Manuscript published: May 9, 2016 (version 1)
  4. Version of Record published: June 13, 2016 (version 2)
  5. Version of Record updated: June 21, 2016 (version 3)

Copyright

© 2016, Rock et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

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Further reading

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    Projections from the basal amygdala (BA) to the ventral hippocampus (vH) are proposed to provide information about the rewarding or threatening nature of learned associations to support appropriate goal-directed and anxiety-like behaviour. Such behaviour occurs via the differential activity of multiple, parallel populations of pyramidal neurons in vH that project to distinct downstream targets, but the nature of BA input and how it connects with these populations is unclear. Using channelrhodopsin-2-assisted circuit mapping in mice, we show that BA input to vH consists of both excitatory and inhibitory projections. Excitatory input specifically targets BA- and nucleus accumbens-projecting vH neurons and avoids prefrontal cortex-projecting vH neurons, while inhibitory input preferentially targets BA-projecting neurons. Through this specific connectivity, BA inhibitory projections gate place-value associations by controlling the activity of nucleus accumbens-projecting vH neurons. Our results define a parallel excitatory and inhibitory projection from BA to vH that can support goal-directed behaviour.

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