Effect of Hypericum perforatum extract on passive avoidance learning of male wistar rats

Ageing could been resulted to increase of oxidative stress that could lead to damage of brain processes including cognitive functions. Since Hypericum extract have increasing effect on brain cognitive functions e.g. learning and memory , it’s effect on passive avoidance learning of male wistar rats were examined.

16 male wistar rats, each weighing about 250-300 g were divided into two groups, control and Hypericum extract group(animals administered with 350 mg/kg/day of Hypericum extract). All of groups had free access to water and food with no limitation. Hypericum extract was administrated orally each day for one week. The passive avoidance learning test was done in the shuttle box 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 decreased staying time in the dark chamber considered as improved passive avoidance learning The data were analyzed by SPSS software and one-way ANOVA followed by the Tuckey test.

In compare to control group, passive avoidance indices were increased significantly. In other words, mean step through latency (STL) of H. perforatum group was 260 seconds and was higher than that of control group (240 seconds) significantly (p< .001).

Our results indicated that administered Hypericum extract could increase passive avoidance learning indices in rats.