Effect of Red Grape Juice on Learning and Passive Avoidance Memory in Rats

Along with increased age, learning and memory being two of the survival necessities decrease and may even deteriorate. This has motivated researches in the field of geriatric medicine to find new medicines effective on learning and memory amplification. Studies have shown that through advanced age, increased oxidative stressors lead to damaged brain processes including cognitive functions. Since types of red grape juice contain antioxidants, this study aimed to examine the effect of this material on passive avoidance memory in 1-year old rats. Twenty rats, each weighing about 270-330 g, were divided into two test and control groups. Both groups with no limitation had access to water vessel. In the control group, the water container contained pure water and in the test group it contained 80% pure water along with 20% grape juice. To prevent modification of ingredients, vessels contents were regularly refreshed. The passive avoidance memory and learning test was done in the learning device following intending treatments for all groups and in similar conditions. In this test, increased time delay for the first time of entry to the dark chamber and sum of the remaining time in the lighted chamber as well as decreased remaining time in the dark chamber indicate improved passive avoidance memory. To data analysis, the Mann-Whitney test was employed. Compared with the control group, learning and passive avoidance memory indices had significantly increased in the test group. Our results show that drinking grape juice causes increased learning and passive avoidance indices in rats; probably the reason was existence of antioxidant substances in the grape juice.