Figure 3. Ameliorative efficacy of oral administration of GE extract on memory impairment. Sprague-Dawley rats were randomly assigned to five different groups (10 rats per group): No treatment, only scopolamine-treated, and GE extract-administered at three different concentrations (50, 250 and 500 mg/kg body weight) with scopolamine-treated. Before learning and memory tests (A, passive avoidance test; B, Morris water maze test), rats were treated according to the experimental group and trained multiple times for a week to escape from the given circumstances. After training, acute memory impairment was induced by an intraperitoneal injection of scopolamine (1 mg/kg of body weight) on the day of the test. (A) Results from the passive avoidance test showed that the escape latency time was maximized to 180 sec for the scopolamine-injected group (control) compared to that for the normal group (69 sec). The latency time was significantly lowered in the groups that received GE extract treatment compared to controls. (B) Data from the Morris water maze test showed that prolonged administration of GE extract to the scopolamine-treated rat hypomnesic model decreased the escape latency time compared to the control group (no GE extract treatment).