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

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.