The effects of daylily on the behaviors and learning memory in the depressed rats / 中华行为医学与脑科学杂志

ABSTRACT

Objective To observe the effects of the extract from daylily on the learning and memory in depression model rats, and to explore its possible mechanism. Methods Rats were randomly divided into control group, model group ( CUMS), the positive group (CUMS + fluoxetine) , high, medium and low dose group (stress + daylily extract in different doses), 12 rats in each group. The depression model was established by combining separation and chronic unpredictable stress. Body mass, open-field-test and sugar consumption experiment were used to evaluate the changes of behaviors in rats. And morris water Maze test was used to evaluate the ability of learning and memory. Results There was no statistically distinction between the rats of each group on weight and the behavioral indicator before modeling. Compared with the control group, the vertical movement,horizontal movement of open box test in the model group were reduced (P＜0.05 ) ,and sugar consumption and preference degree decreased (P<0.05 ).The target quadrant time, platform resident time, effective area residence time and crossing platform times in the water maze test of the model group was less than those of the control group. The daylily effect was evaluated at 0, 7, 14, 21, 28, 35, 42 days respectively post treatment. There were significant differences in depression behaviors between model group and daylily group(P＜0.05). And each indicator in the water maze test of the daylily group (high, medium dose) was more than that of model group (P ＜ 0. 05). Control group, model group, positive group, high, medium and low dose group, vertical movement scores were (41.83 ± 17.63; 8.14 ±4.23; 12.73 ±7.21; 23.17 ± 18.75; 8.38 ±3.46; 13.50 ±5.44); horizontal movement scores were (69.92 ±34.04; 28.33 ±20.36; 62.25 ± 15.72; 69.42 ±35.17 ; 49.08 ±32.85; 48.08 ±21.19). Conclusion Daylily may be partially work on the depression of rats, with some antidepressant effect, meantime,daylily can improve the ability of learning and memorizing of the depressed rats.