Effect of Hydroalcoholic Extract of Stachys lavandulifolia on Pentylenetetrazole-induced Seizures in Male Mice: The Role of GABAergic and Opioidergic Systems

Epilepsy is one of the most common neurological disorders. Though there are several effective drugs for treating epilepsy, most drugs are associated with side effects and drug interactions. Stachys lavandulifolia used in Iranian traditional medicine has proven anti-anxiety and sedative properties. The current study aimed to evaluate the anticonvulsant effect of hydroalcoholic extract of S. lavandulifoliaon the Pentylenetetrazole (PTZ)-induced seizure in male mice and the role of benzodiazepine and opioid receptors. 

This study was conducted on 100 male mice, randomly categorized into 10 groups: Normal Saline (NS), two diazepam groups (0.025 and 0.1 mg/kg), three S. lavandulifolia extract groups (50, 100, and 200 mg/kg), diazepam 0.025 mg/kg+S. lavandulifolia extract 50 mg/kg, and three groups that pretreated with NS, flumazenil, or naloxone, 5 min before injection of 200 mg/kg S. lavandulifolia extract. After 30 min, PTZ (80 mg/kg) was injected into animals, and seizure indices were evaluated. 

The S. lavandulifoliaextract attenuated the PTZ-induced seizures in a dose-dependent manner, and pretreatment with flumazenil reversed this effect. However, pretreatment with naloxone could not reverse this effect because seizure indices in the naloxone pretreated group were lower than that in the normal saline group. The combination of an ineffective dose of diazepam and S. lavandulifoliaextract decreased PTZ-induced seizures. 

The results of our study showed the anticonvulsant properties of hydroalcoholic extract of S. lavandulifolia. These effects might be due to the impact of the components of this extract on the central benzodiazepine system.