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ISSN 2522-9028 (Print)
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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. 2020; 66(2-3): 21-26

Nonsynaptic epileptiform activity in CA3-CA1 regions of the hippocampus in low-Ca2+ and Cd2+-containing milieu

O.S. Zapukhliak, O.V. Netsyk, D.S. Isaev

  1. Bogomoletz Institute of physiology NAS of Ukraine, Kyiv, Ukraine


In our work we compare seizure-like-activity in CA1 and CA3 regions of the hippocampus in two common models of nonsynaptic epilepsy in vitro: low-Ca2+ and Cd2+ models. Under low-Ca2+ conditions, the concentration of Ca2+ is insufficient to produce synaptic release. Cd2+ ions block Ca2+ channels, which result in a decrease of intracellular concentration of Ca2+ in presynaptic sites. We found that delay time for seizure appearance in CA1 area is longer than in CA3 in both models. The frequency of epileptic-like discharges in low-Ca2+ model was higher than in Cd2+-model. We did not find a difference in patterns of seizure-like discharges, which suggests a similar mechanism explored in studied models. The difference in distribution and frequency of nonsynaptic seizure-like activity in the hippocampus is discussed in the paper.

Keywords: nonsynaptic epileptiform activity; low-Ca2+ model of seizures; CA3-CA1 regions of the hippocampus; rat brain slices.


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