Abstract
This study investigated the potential anticonvulsant effect of C. intybus and T. serotinum against the maximal electroshock (MES), pentylenetetrazole (PTZ) and strychnine nitrate (STN)- induced seizure models in 21-day-old rats. Moreover, acute toxicity studies (LD50) were performed after oral administration of the tested extracts to rats in graded doses. LD50 values of both extracts in rats were more than 4000 mg/kg. In the MES model, the administration of 200 mg/kg of C. intybus resulted in the complete abolition of HLTE in 60% of the rats and this was increased to 70% with the administration of 300 mg/kg. The protective effect of T. serotinum extract (300 mg/kg) against HLTE of rats was 50%. C. intybus extract at doses of 200 and 300 mg/kg increased the latency to the seizure onset in PTZ model to 116.4 and 144.7 s, respectively (vs 55.2 s in control group). Similarly, T. serotinum (300 mg/kg) prolonged the latency to the seizure onset to 114.7 s. In the same model, 60 and 90% of rats were protected against mortality with 200 and 300 mg/kg, respectively of C. intybus and 50% with 300 mg/kg of T. serotinum. Both extracts failed to protect rats against STN-induced seizures. C. intybus at a dose of 100 mg/kg and T. serotinum at 200 and 300 mg/kg failed to protect rats against MES, PTZ and STN seizures. The present study suggests that the C. intybus and T. serotinum extracts may produce their anticonvulsant effects via non-specific mechanisms since they abolished the HLTE induced by MES as well as delayed the latency of seizures produced by PTZ.