Anxiety is among the most common disorders affecting a great number of people. Different neurotransmitter systems, such as GABAergic system, play an important role in emergence of anxietyrelated behaviors. In this study, we have investigated the effect of Citrus aurantium L. essential oil on anxiety and its interaction with GABAergic pathways. Male mice were assigned into control, sham, and experimental groups. Intraperitoneal injection of Citrus aurantium L. essential oil was applied at doses of 0.5, 2.5, and 5 percent for 5 days. Diazepam (0.1 mg/kg) was injected on the fifth day, thirty minutes before applying Citrus aurantium L. essential oil. The anxiety-related behavior of mice was then assessed using elevated plus-maze test. In groups receiving Citrus aurantium L. essential oil at doses of 2.5 and 5 percent, the percent time spent in the open arms increased significantly (P < 0.001). The injection of diazepam alone or with Citrus aurantium L. essential oil resulted in increasing in the number of entries to the open arms and the percent time spent in the open arms (P < 0.001). The results of this study show that Citrus aurantium L. essential oil can reduce anxiety-related behaviors in male mice thah may act via GABAergic system.

Biebersteinia multifida DC. has been used for the purpose of development of physical strength in iranian folk medicine. In the present study, we investigated the effect of Biebersteinia multifida DC. root extract on performance of the Forced Swimming Test (FST), and on blood biochemical parameters related to fatigue: Blood Urea Nitrogen (BUN), Creatine Kinase (CK), Lactic Dehydrogenase (LDH), Glucose (Glc), and Total Protein (TP). Biebersteinia multifida DC. root extract was orally administered to mice at the doses 4, 7 and 10 mg/kg continuously once per day for 1 and 7 days using a feeding atraumatic needle. After 7 days, on FST the immobility time was decreased in the treated-groups at the doses 4 and 7 mg/kg, but after 1 day, only the immobility time of the treatedgroup at the dose of 4 mg/kg was decreased significantly. In addition, the content of Glc and TP in the blood serum was significantly increased in the groups receiving 4 and 7 mg/kg of Biebersteinia multifida DC. root extract for 7 days and LDH was decreased significantly. However, the levels of BUN and CK did not show a significant change. The results predict a potential benefit of Biebersteinia multifida DC. root extract as an anti-fatigue treatment and for improving physical stamina.

Due to our previous findings about the role of GABAegic neurotransmission in anxiolytic effects of Citrus aurantium L. essential oil, we are now presenting flomazenil interaction with this herb, as an antagonist of benzodiazepines at GABA receptor. The study was performed on 84 male albino mice assigned to 14 groups of six. The animals were injected intraperitoneally with the Citrus aurantium L. essential oil for 5 days. On the fifth day, either normal saline or flomazenil (0.1 mg/kg) was injected to the experimental groups. Thirty minutes after the injection, all the groups were assessed for anxiety-related behavior by elevated plus-maze test. In groups receiving Citrus aurantium L. essential oil at doses of 2.