Intracellular Zn2+ signaling in the dentate gyrus is required for object recognition memory. Issue 11 (4th July 2014)

• Record Type: Journal Article
• Authors: Takeda, Atsushi; Tamano, Haruna; Ogawa, Taisuke; Takada, Shunsuke; Nakamura, Masatoshi; Fujii, Hiroaki; Ando, Masaki
• Is Part Of: Hippocampus. Volume 24:Issue 11(2014:Nov.)
• Page Start: 1404
• Page End: 1412
• Publication Date: 2014-07-04
• Subjects: Hippocampus (Brain) -- Periodicals; 612.825
• DOI: 10.1002/hipo.22322
• Languages: English
• ISSNs: 1050-9631

Abstract

<abstract abstract-type="main"> <title>ABSTRACT</title> <p>The role of perforant pathway‐dentate granule cell synapses in cognitive behavior was examined focusing on synaptic Zn<sup>2+</sup> signaling in the dentate gyrus. Object recognition memory was transiently impaired when extracellular Zn<sup>2+</sup> levels were decreased by injection of clioquinol and <italic>N</italic>, <italic>N</italic>, <italic>N</italic>′, <italic>N</italic>′<bold>‐t</bold>etrakis‐(2‐pyridylmethyl) ethylendediamine. To pursue the effect of the loss and/or blockade of Zn<sup>2+</sup> signaling in dentate granule cells, ZnAF‐2DA (100 pmol, 0.1 mM/1 µl), an intracellular Zn<sup>2+</sup> chelator, was locally injected into the dentate molecular layer of rats. ZnAF‐2DA injection, which was estimated to chelate intracellular Zn<sup>2+</sup> signaling only in the dentate gyrus, affected object recognition memory 1 h after training without affecting intracellular Ca<sup>2+</sup> signaling in the dentate molecular layer. <italic>In vivo</italic> dentate gyrus long‐term potentiation (LTP) was affected under the local perfusion of the recording region (the dentate granule cell layer) with 0.1 mM ZnAF‐2DA, but not with 1<bold>–</bold>10 mM CaEDTA, an extracellular Zn<sup>2+</sup> chelator, suggesting that the blockade of intracellular Zn<sup>2+</sup> signaling in dentate granule cells affects dentate gyrus LTP. The present study demonstrates that intracellular Zn<sup>2+</sup> signaling in the dentate gyrus is required for object recognition memory, probably via dentate gyrus LTP expression. © 2014 Wiley Periodicals, Inc.</p> </abstract>