EFFECTS OF GINSENOSIDES ON IMPAIRED PERFORMANCE CAUSED BY SCOPOLAMINEIN RATS

The effects of five structurally different ginsenosides on the perform ance impaired by scopolamine in rats were studied in a radial-arm maze . Ginsenoside Re had an ameliorating effect, but the ginsenosides, 20- O-glucosyl-protopanaxadiol, F2, Rf, and Rh1, did not. We reported prev iously that ginsenoside Rg1 had an ameliorating effect but that ginsen osides Rbl and Rd did not (Yamaguchi et al., 1995, Psychoneuroendocrin ology 20, 645). The sugar moieties at C(6) and C(20), which are posses sed by Re and Rg1, seem to be indispensable for an ameliorating effect on the performance impaired by scopolamine.