1. Introduction
eizure is caused by the abnormal discharge of brain neurons that originate from one area and spread to other areas. Epilepsy is called the occurrence of unpredictable periodic and recurrent seizures [1]. Besides, it has approximately involved 0.5%-1% of the world’s population [2]. Medicinal plants have been the primary source of medicines and rich sources of secondary metabolites with biological activities [3]. 
Ocimum basilicum is a medicinal plant with flavonoids and flavone compounds as well as antioxidant and anti-inflammatory properties. Considering the anticonvulsant role of antioxidant and anti-inflammatory agents [4], this study aimed to evaluate the anticonvulsant effects of hydro-alcoholic extract of Ocimum basilicum green leaf on Pentylenetetrazol (PTZ)-induced seizure in male mice.
2. Methods
In this experimental study, 48 albino male mice, weighing 20-25 g were randomly divided into 6 groups. All study groups were injected Intraperitoneally (IP). The negative and positive control groups received saline (10 ml/kg) and phenobarbital (40 mg/kg), respectively. The treatment groups received doses of 100, 300, 500, and 1000 mg/kg of hydro-alcoholic extract of Ocimum basilicum green leaf. To provoke convulsion, after 45 minutes, PTZ was injected (80 mg/kg) to all study groups; accordingly, the initiation time of myoclonic and tonic-clonic seizures and frequency of 24h death was measured.
3. Results
The current research results indicated that the extract delayed the initiation time of myoclonic and tonic-clonic seizures, compared to the control group. The delay was significant at doses of 1000 (P<0.001), 500, and 300 mg/kg (P<0.01) for myoclonic seizure (Figure 1) as well as 1000, 500, and 300 mg/kg (< 0.001) and 100 mg/kg (P<0.05) for tonic-clonic seizure.  Additionally, the extract decreased the 24h death rate. This was significant at doses of 1000, 500, and 300 mg/kg (P<0.001).
4. Discussion and Conclusion
The present study data indicated that the hydro-alcoholic extract of Ocimum basilicum green leaf effectively reduced PTZ-induced seizures. The extract increased the latency of myoclonic and tonic-clonic seizures and decreased the frequency of mortality 24h after PTZ injection. Substances that inhibit convulsions or increase the latency of PTZ-induced seizures are suggested as having anticonvulsant activity [5]. Therefore, the demonstration of Ocimum basilicum activity on the seizure model suggests that this herb possesses anticonvulsant potential.  

Ethical Considerations
Compliance with ethical guidelines
In this study, all steps of working with laboratory animals were performed according to the ethics guidelines of working with laboratory animals of Guilan University of Medical Sciences (Code: IR.GUMS.REC.1394.608).

Funding
This project was financially supported by the Vice-Chancellor Reseach and Technology of Guilan University of Medical Sciences.

Authors' contributions
Conducting experiments, collecting data and writing: Athena Rahimipour; Experimental design, data analysis and review, editing and finalization: Mohammad Rostampour.

Conflicts of interest
The authors declared no conflicts of interest.

Acknowledgements
The authors greatly appreciate the Vice-Chancellor Research and Technology of Guilan University of Medical Sciences for support and the Department of Medicinal Plants of Shahid Beheshti University and Ali Sonboli for preparing the extract of the plant.


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