Structural development and dorsoventral maturation of the medial entorhinal cortex

  1. Saikat Ray  Is a corresponding author
  2. Michael Brecht
  1. Humboldt University of Berlin, Germany

Abstract

We investigated the structural development of superficial-layers of medial entorhinal cortex and parasubiculum in rats. The grid-layout and cholinergic-innervation of calbindin-positive pyramidal-cells in layer-2 emerged around birth while reelin-positive stellate-cells were scattered throughout development. Layer-3 and parasubiculum neurons had a transient calbindin-expression, which declined with age. Early postnatally, layer-2 pyramidal but not stellate-cells co-localized with doublecortin- a marker of immature neurons- suggesting delayed functional-maturation of pyramidal-cells. Three observations indicated a dorsal-to-ventral maturation of entorhinal cortex and parasubiculum: (i) calbindin-expression in layer-3 neurons decreased progressively from dorsal-to-ventral, (ii) doublecortin in layer-2 calbindin-positive-patches disappeared dorsally before ventrally, and (iii) wolframin-expression emerged earlier in dorsal than ventral parasubiculum. The early appearance of calbindin-pyramidal grid-organization in layer-2 suggests that this pattern is instructed by genetic information rather than experience. Superficial-layer-microcircuits mature earlier in dorsal entorhinal cortex, where small spatial-scales are represented. Maturation of ventral-entorhinal-microcircuits- representing larger spatial-scales - follows later around the onset of exploratory behavior.

Article and author information

Author details

  1. Saikat Ray

    Bernstein Center for Computational Neuroscience, Humboldt University of Berlin, Berlin, Germany
    For correspondence
    saikat.ray@bccn-berlin.de
    Competing interests
    The authors declare that no competing interests exist.
  2. Michael Brecht

    Bernstein Center for Computational Neuroscience, Humboldt University of Berlin, Berlin, Germany
    Competing interests
    The authors declare that no competing interests exist.

Ethics

Animal experimentation: All experimental procedures were performed according to the German guidelines on animal welfare under the supervision of local ethics committees (LaGeSo) under the permit T0106 - 14.

Reviewing Editor

  1. Howard Eichenbaum, Boston University, United States

Publication history

  1. Received: November 26, 2015
  2. Accepted: March 27, 2016
  3. Accepted Manuscript published: April 2, 2016 (version 1)
  4. Accepted Manuscript updated: April 7, 2016 (version 2)
  5. Version of Record published: April 22, 2016 (version 3)

Copyright

© 2016, Ray & Brecht

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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  1. Saikat Ray
  2. Michael Brecht
(2016)
Structural development and dorsoventral maturation of the medial entorhinal cortex
eLife 5:e13343.
https://doi.org/10.7554/eLife.13343
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