Improvement of learning ability in mice and rats with the root extract of dinh lang (Policias fruticosum L.).

The effect of Dinh lang root extract (DLRE) on the learning ability of mice and rats was studied. The learning performance in groups of rats belonging to different age-cohorts (4-6 months, 16-18 months and 22-24 months) was studied in the shuttle-box and the age-related decline in the acquisition of a conditioned avoidance response (CAR) was established. Using the passive avoidance test also in mice, an age-related decay in performance, was detected. DLRE treatment 10 mg/kg daily for 3-4 weeks restored the lost ability of 22-24 months old rats to develop CAR, the same treatment significantly improved the performance of young mice and improved retention in both 5-months old and 19-20 months old groups of mice.