In a previous study, we reported that ginseng extract has anxiolytic-like effects in the elevated plus-maze model and that the ginseng saponin fraction plays an important role. This experiment was performed to investigate the anxiolytic-like effects of ginsenosides Rb 1 , Rg 1 , Rg 3 -R, and Rg 3 -S, and the Rg 5 and Rk mixture isolated from the ginseng saponin fraction in the elevated plus-maze. Furthermore, the anxiolytic-effects of Rb 1 , Rg 1 , Rg 3 -R, Rg 3 -S, and the Rg 5 and Rk mixture

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... ere compared with those of a well-known active anxiolytic drug ( diazepam). The oral administration of ginsenoside Rb 1 significantly increased the number of open arm entries and the time spent on the open arm compared with those in the vehicle-treated group. Ginsenoside Rg 1 and the Rg 5 and Rk mixture also significantly increased the number of open arm entries and the time spent on the open arm. However, ginsenosides Rg 3 -R and Rg 3 -S did not increase the number of open arm entries or the time spent on the open arm. On the other hand, ginsenoside Rb 1 and the Rg 5 and Rk mixture decreased locomotor activity in a manner similar to diazepam. These data indicate that ginsenosides Rb 1 , Rg 1 , and the Rg 5 and Rk mixture have anxiolytic-like effects, but ginsenosides Rg 3 -R and Rg 3 -S do not in this model. We provide evidence that some ginsenosides may be useful for the treatment of anxiety.