Evaluation of isolated and combined effects of riluzole and sodium valproate in genetic absence epilepsy rats

Year 2025, Volume: 38 Issue: 1, 68 - 75, 29.01.2025

Tuğba Karamahmutoğlu , Eren Şahin , Bahattin Gürbüz , Türkan Şükürov Ayşe Nazlı Güneş Ege Fakı Rezzan Gülhan , Zeynep Us

https://doi.org/10.5472/marumj.1629028

Abstract

Objective: In epilepsy treatment, drugs that increase GABAergic and decrease glutamatergic activity, like sodium valproate, are used.
Riluzole is a neuroprotective drug that blocks glutamatergic neurotransmission and is a potential drug with its anti-seizure effects. This
study evaluates the anti-seizure effects of sodium valproate and riluzole on the genetic absence epilepsy rat from Strasbourg (GAERS)
model individually and combined.
Materials and Methods: Adult male GAERS rats (n = 22) were used. Rats were administered 5/10 mg/kg riluzole, 150/300 mg/kg
sodium valproate, 95% ethanol, and 5 mg/kg riluzole combinations with 150-300 mg/kg sodium valproate intraperitoneally. EEG
recordings and locomotor activity tests were conducted. Statistical analysis was performed using GraphPad Prism.
Results: Post-injection of 10 mg/kg riluzole significantly decreased the number of spike-wave-discharges (SWDs) (p = 0.04) compared
to the control group. A synergistic effect was observed with 5 mg/kg riluzole and 150 mg/kg sodium valproate, reducing total seizure
time (p = 0.03) and SWDs (p = 0.03).
Conclusion: The study demonstrated the anti-seizure effects of 150/300 mg/kg sodium valproate, 10 mg/kg riluzole, and ethanol. A
synergistic effect of 5 mg/kg riluzole with 150 mg/kg sodium valproate was noted. As an isolated or combined solution, riluzole shows
potential, especially in resistant epilepsy treatment.

Keywords

GAERS, Riluzole, Sodium valproate, Absence epilepsy, Anti-seizure, Ethanol

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