Abstract

The putative anxiolytic activity of the white and red varieties of ginseng, the root of Panax ginseng, was investigated in rats and mice using a number of experimental paradigms of anxiety and compared with that of diazepam. Pilot studies indicated that single-dose administration of ginseng had little to no acute behavioural effects, hence the two varieties of ginseng were administered orally at two dose levels twice daily for 5 days, while diazepam (1 mg/kg, i.p.) was administered acutely. White and red varieties of ginseng (20 and 50 mg/kg) showed positive results when tested against several paradigms of experimental anxiety. Both were effective in the open-field and elevated plus-maze tests and reduced conflict behaviour in thirsty rats and footshock-induced fighting in paired mice. Ginseng also attenuated pentylenetetrazole-induced decrease in rat brain MAO activity, confirming its anxiolytic activity since this has been proposed to be an endogenous marker for anxiety. The effects induced by white and red ginseng (50 mg/kg x 5 days) were comparable to those induced by diazepam (1 mg/kg).