Surface charge impact in nonsynaptic model of epilepsy in rat hippocampus
O.S. Zapukhliak, V.О. Kachanovska, E.V. Isaeva, O.V. Netsyk, D.S. Isaev
O.O.Bogomoletz Institute of Physiology of National Academy of Science of Ukraine, Kyiv, Ukraine
DOI: https://doi.org/10.15407/fz62.02.035

Abstract
Decreasing of surface charge screening near voltage-gated ion channels via reduction of extracellular
cation divalent ions provide potent mechanism of altering cellular excitability and seizure threshold.
Spontaneous field potentials were recorded from horizontal brain slices of young Wistar rats (postnatal day
10-12). Extracellular registrations wereobtained from CA1 and CA3 area of hippocampus. For induction
of nonsynaptic epileptiform activity slices were perfused with artificial cerebrospinal fluid with omitted
Ca2+and Mg2+ ions. Effect of different Mg2+ concentration (1, 2, and 3mmol/l) on initial stage of nonsynaptic
epileptiform discharges was studied. Our results suggest that the change in Mg2+ concentration dramatically
affects the probability of induction of low-Ca2+seizure-like activity (SLA), providing evidence that Mg2+
can alter cerebral excitability by affecting the surface charge and supporting the idea that surface charge
could be a pharmacological target for anti-epileptic treatment.
Keywords:
low-Ca2+ seizure-like activity; surface charge; magnesium; hippocampus.
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