Elsevier

Brain Research

Volume 322, Issue 1, 19 November 1984, Pages 167-171
Brain Research

Chronically elevating plasma Mg2+ improves hippocampal frequency potentiation and reversal learning in aged and young rats

https://doi.org/10.1016/0006-8993(84)91199-5Get rights and content

Abstract

One prediction of the hypothesis that the capacity for hippocampal frequency potentiation is relevant to behavioral plasticity is tested in this study, by chronically elevating magnesium in intact aged and young rats. Elevated extracellular Mg2+ specifically improves frequency potentiation in hippocampal slices, and chronic alterations in plasma Mg2+ can increase brain Mg2+ in intact animals. Aged and young rats on a diet that elevated plasma Mg2+ exhibited stronger frequency potentiation under urethane anesthesia, and showed improved maze reversal learning.

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    This work was supported by Grants AG 01737 and AG 04542 from the N.I.H.

    *

    Present address: University of Florida, School of Medicine Gainesville, FL 32601, U.S.A.

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