State-Dependent Effect of Interictal Epileptiform Discharges

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68407700%3A21230%2F18%3A00325736" target="_blank" >RIV/68407700:21230/18:00325736 - isvavai.cz</a>

Result on the web

<a href="http://dx.doi.org/10.1111/epi.14612" target="_blank" >http://dx.doi.org/10.1111/epi.14612</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1111/epi.14612" target="_blank" >10.1111/epi.14612</a>

Result language

angličtina

Original language name

State-Dependent Effect of Interictal Epileptiform Discharges

Original language description

Purpose: The impact of interictal epileptiform discharges (IEDs) on ictogenesis is not well understood. Previous studies demonstrated that IEDs have the capacity to promote transition to seizure but also the presence of IEDs is able to delay or prevent seizure genesis. Using computer modeling, we have demonstrated that the pro-ictogenic or anti-ictogenic nature of IEDs depends on the state of stability of the ictogenic network. In this study, we have explored this theory in in vitro model of seizures. Method: Isolated CA1 slices were perfused with artificial CSF containing high potassium (>8 mM). Field potentials from the hippocampal CA1 were recorded using extracellular electrodes. Interictal perturbations mimicking IEDs were delivered by stimulation of Schaffer collaterals. Results: The CA1 network was perturbed with 1 Hz stimuli initiated after the end of the seizure. This stimulation has the capacity to delay seizure onset by increasing the duration of the interictal period (>50% increase, n=41/7 stimulations/slices). Prolongation of interictal period positively correlated with the duration of the stimulation (r = 0.97, 95% CI [0.62 0.99]). To evaluate the observation that pro-seizure effect of IED occurs when the neural network is unstable, we have delivered a single stimulus either early after previous seizure or just before the next seizure. Only 38 % of early stimulations with the intensity of 300 µA were able to induce seizure (n=3/8 stimulations). In contrary, preictal stimulation with the intensity of 200 µA and 300 µA induced seizure in all cases (6/6 and 4/4 stimulations respectively). Conclusion: IEDs display anti-seizure effect if they are delivered when the neural network is stable. The pro-ictogenic effect occurs if the network exists in a less stable state characterized by high sensitivity to perturbations. Results may have implications for design and optimization of brain stimulation therapy to control epilepsy and transition to seizure.

Czech name

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Czech description

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Type

O - Miscellaneous

CEP classification

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OECD FORD branch

20601 - Medical engineering

Project

Result was created during the realization of more than one project. More information in the Projects tab.

Continuities

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Publication year

2018

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů