Anti-anxiety effect of Alpha-pinene in comparison with Diazepam in adult male rats

Considering the side effects of anti- anxiety drugs, this study investigated the effect of alpha-pinene on anxiety behaviors compared with Diazepam in rats.

In this study, 40 male Wistar rats were divided into 5 groups: control, sham (received alphapinene solvent), the groups received 2 and 4 mg/kg alphapinene, and the group that received diazepam 10 mg/kg. At the end of this period, anxiety was measured using elevated plus maze and concentrations of malondialdehyde, thiol and glutathione peroxidase, in hippocampal tissue. The results were analyzed using one-way ANOVA and Tukey tests.

In the groups receiving 2 and 4 mg/kg doses of alpha-pinene significantly increased the percentage of open arm entry (P<0.001) and percentage of time spent in the open arm (P<0.05) (P<0.05). Compared to the control and diazepam groups, administration of alpha-pinene significantly decreased MDA concentration (P<0.001) and significant increase in thiol (P<0.01) (P<0.05) and glutathione peroxidase enzyme activity was evident (P<0.001).

Alpha-pinene showed a downward effect on anxiety responses in male rats, similar to anxiolytic effects of diazepam. Alpha-pinene may be potentiated by binding to the position of benzodiazepines in GABA A receptors and exerted its anti-anxiety effect with antioxidant properties.