The effect of riluzole alone and in combination with sodium valproate on pentylenetetrazole induced seizures in swiss-albino rats

Amol Ramrao Jadhav, Kiran Prabhakar Vakade, Bana Bihari Nayak, Vijayaprasad M. Sangisetti, Vijaykumar N. Abhavathi


Background: Riluzole- a glutamate antagonist is known to enhance antiepileptic effects of various other antiepileptic drugs. The present study was undertaken to evaluate anticonvulsant effect of riluzole alone and in combination with sodium valproate on pentylenetetrazole (Metrazol) induced seizures in swiss-albino rats.

Methods: Pentylenetetrazole (PTZ) 50 mg/kg intraperitonially (ip) was used to induce seizure in swiss- albino rats. Anticonvulsant effect of riluzole (at 5 mg/kg and 10 mg/kg) and sodium valproate (at 75 mg/kg, 150 mg/kg and 300 mg/kg) was studied on PTZ induced seizures in albino rats. Also effect of riluzole (10mg/kg) in combination with sodium valproate (75 mg/kg, 150 mg/kg and 300 mg/kg) was studied.  Parameters such as time of onset of first clonic convulsion in seconds, frequency of clonic convulsion in 60 minute and total duration of entire convulsion in minutes were studied. For statistical analysis unpaired t test was used.

Results: At 5 mg/kg and 10 mg/kg doses riluzole per se was not found to produce any significant effect in PTZ induced seizures (P>0.05). Sodium valproate at 300 mg/kg dose was found to produce significant antiepileptic effect (P<0.001) but not at 75 mg/kg and 150 mg/kg dose (P>0.05). Interestingly significant antiepileptic effect was noted with combination of riluzole (at 10 mg/kg) with sodium valproate at 150 mg/kg and 300 mg/kg dose (P<0.001).

Conclusions: Riluzole alone was not found to produce any significant protective effect against PTZ induced seizures in albino rats. However riluzole (10 mg/kg) was found to enhance the antiepileptic activity of sodium valproate.


Riluzole, PTZ induced seizure, Antiepileptic, Convulsions

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