Age‐ and individual‐related specificities in the effects of standardized ginseng extract on learning and memory (experiments on rats)

Using a two‐way active avoidance with punishment (electric shock) reinforcement (shuttle box) we investigated the effects of Panax ginseng extract, standardized according to the content of ginsenosides on learning and memory in 2‐, 10‐, and 22‐month old Wistar rats and in rats of the same age (5‐month old) which, after a preliminary training with the same method, had been classified as ‘good’, ‘poor’ and ‘satisfactory’ learners. In experiments on rats of different ages G115 was administered orally daily for 10 consecutive days before training at increasing doses of 3, 10, 30 and 100 mg/kg body weight. The animals were trained for 5 days and the retention test was given 14 days after the last administration of G115 (10 days after the last training session). In experiments on rats with different learning capabilities G115 was administered orally at a dose of 10 mg/kg for 10 days after shuttle box training. The retention test was performed on the day following the last treatment with G115. It was found that G115 exerted the most favourable effects on learning and memory when these processes were decayed as a result either of senescence or of individual specificities.