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ISSN 2522-9028 (Print)
ISSN 2522-9036 (Online)
DOI: https://doi.org/10.15407/fz

Fiziologichnyi Zhurnal

is a scientific journal issued by the

Bogomoletz Institute of Physiology
National Academy of Sciences of Ukraine

Editor-in-chief: V.F. Sagach

The journal was founded in 1955 as
1955 – 1977 "Fiziolohichnyi zhurnal" (ISSN 0015 – 3311)
1978 – 1993 "Fiziologicheskii zhurnal" (ISSN 0201 – 8489)
1994 – 2016 "Fiziolohichnyi zhurnal" (ISSN 0201 – 8489)
2017 – "Fiziolohichnyi zhurnal" (ISSN 2522-9028)

Fiziol. Zh. 2017; 63(2): 10-16


Effect of altered extracellular magnesium concentration on the neuronal activity in different hippocampal regions of immature rats

A.Vlasiuk, A. Romanov, D. Isaev, E. Isaeva

    O.O.Bogomoletz Institute of Physiology of National Academy of Science of Ukraine, Kyiv
DOI: https://doi.org/10.15407/fz63.02.010

Abstract

Using acute hippocampal slice preparation dissected from immature rats, we investigated the effect of lowering Mg2+ concentration in the extracellular solution on the probability to evoke epileptiform activity in different regions of hippocampus. Electrophysiological recordings revealed different patterns of such activity in hippocampal CA1 region. In agreement with studies on the adult rat hippocampus probability to induce epileptiform activity by means of lowering Mg2+ concentration was increased in the ventral part of hippocampus (VH) compared to dorsal part (DH). We also found a significant increase in probability to induce ictal-like activity (ILE) in both hippocampal regions compared to results obtained in adult rats with a higher rate of ILE incidence in VH (90 %) compared to DH (50 %). Our experiments with cuts of hippocampal fiber pathways showed that in VH, ILE originated in CA1 region and propagated to CA3 region and dentate gyrus, while interictal-like activity originated in CA3 region. Possible mechanisms of the region specificity of the development of epileptiform activity in the immature hippocampus discussed.

Keywords: epileptiform activity; dorsal and ventral hippocampus; immature rat

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