Comparison of the anxiolytic effects of diazepam and kava on behaviour in rats.

Abstract

Due to the scarcity of research on kava in animal populations, the current study aimed to cover weaknesses in previous investigations in this area by comparing the anxiolytic effects of chronic kava and diazepam treatment on male and female rats. 90 mg/kg and 180 mg/kg of kava, and 5 mg/kg and 10 mg/kg of diazepam were administered through food daily to 40 male and 40 female PVG/c rats over a period of four weeks. During treatment the rats were tested on three animal models of anxiety; the open field, light dark box, and elevated plus maze. Few significant dose effects occurred for either kava or diazepam. In the elevated plus maze both the 90 mg/kg and 180 mg/kg kava dose groups spent more time in the open arms compared to the control group, suggesting that both doses had an anxiolytic effect, but this was the only dose effect found for kava. A sex X dose interaction for diazepam occurred for males in the open field, as males in the 10 mg/kg dose group spent more time in the corner squares than the 5 mg/kg dose group. Another interaction effect occurred for female rats in the open field, as female controls walked more often than those in the 10 mg/kg dose group. In the light dark box female rats in the 5 mg/kg dose group and the control group entered the light side more times than those in the 10 mg/kg dose group, and the control and 5 mg/kg dose group entered the light side more often than those in the 10 mg/kg overall. These results did not allow meaningful comparisons between kava and diazepam to be made, but suggested that a chronic 10 mg/kg/day dose of diazepam may not be as effective as a lower dose. Future research comparing the two substances is recommended.