Background and Aim: Anxiety is a common disorder that many solutions and various drugs have been provided for its treatment. Since medicinal plants have fewer side effects, in this study, we investigated the effect of seed extract of Pimpinella anisum on anxiety in gonadectomized male rats.

Material and Methods: After gonadectomy, 32 male Wistar rats weighting 230±20 g, were randomly divided into four groups: positive control group which received saline, and experimental groups which received 250, 300 and 400 mg/kg of Anise extract, ip.  30 minutes after injection, anxiety was evaluated by using elevated plus maze and anxiety indices (time spent in open arms and number of open arm entries) were recorded for 5 minutes. Data were analyzed by ANOVA and Tukey test.

Results: The results showed a significant increase in the duration of open arms at the doses of 300 & 400 mg/kg and also a significant increase in the number of open arm entries at the dose 400 mg/kg. None of these doses showed any effects on motor activity.

Conclusion: The results indicated that the Anise seed extract, probably by its phytosterols compounds, induced neurosteroids synthesis in the brain and reduced anxiety by stimulating GABA receptors.

Keywords: Anxiety, Elevated plus maze, Anise extract, Gonadectomy.

Received: Feb 28, 2015      Accepted: Jun 28, 2015