The involvement of adrenergic system in the anxiolytic effect of hydro-alcoholic extract of Valeriana officinalis in male mice

Previous studies have shown that valerian extracts induces anxiolytic and sedative effects via the interference with GABAergic system. Since, central adrenergic system plays an important role in the anxiety-related behaviors, this study aimed to investigate the involvement of this system in the anxiolytic effect of hydro-alcoholic extract of Valeriana officinalis in adult male mice. In this study, 63 mice were randomly divided into seven groups. Anxiety-related behaviors of mice were evaluated using the elevated plus maze by recording of the percentage of time the mice spent in the open arm and percentage of open arm entry. All drugs (saline, valeriana extract and epinephrine) were injected intraperitoneally 30 minutes before the test of anxiety. The valeriana extract decreased the anxiety-related behavior by increasing the percentage of time spent in the open arm and percentage of open arm entry. Epinephrine, when injected before the extract, decreased the anxiolytic effect of valeriana extract, whereas the same dose of epinephrine alone did not have any significant effect on the anxiety. It seems that the central adrenergic mechanisms may probably involve in the effect of hydro-alcoholic extract of valeriana on the reduction of the anxiety-related behaviors in mice.