衰老对应激前后小鼠抑郁及焦虑样行为的影响

目的:探讨不同年龄段小鼠应激造模前后的抑郁及焦虑样行为.方法:54只C57BL/6J小鼠分为正常对照(NC)组和慢性束缚应激(CRS)组,再根据年龄分为青年亚组、中年亚组、老年亚组,共6亚组,每亚组9只.通过检测各组小鼠的行为学改变,包括体质量、悬尾试验、强迫游泳试验、糖水偏好试验、开放旷场实验,观察小鼠抑郁样及焦虑样...

Effect of Aging on Depressive-Like and Anxiety-Like Behaviors in Mice before and after Stress

To explore the depressive-like and anxiety-like behavior of mice at different ages before and after modeling. Methods: A total of 54 C57BL/6J mice were divided into the normal control (NC) group and chronic restraint stress (CRS) group, and each group was divided into 3 subgroups according to age, including young subgroup, middle-aged subgroup, and old subgroup, for a total of 6 subgroups with 9 mice in each. The behavioral changes of mice in each group were studied through assessing the body weight, tail suspension test, forced swimming test, sugar preference test, and open field test to evaluate the depressive-like and anxiety-like behavior of the mice. Results: Within the NC group, compared with that of the young subgroup, the frequency of rearing behavior of the middle-aged subgroup was significantly decreased (P<0.05); the body weight of the old subgroup was significantly increased (P<0.05), the immobility time during tail suspension and forced swimming was significantly decreased (P<0.05), and the total distance traveled and frequency of rearing behavior in the open field were significantly decreased (P<0.05). Compared with that of the NC group, body weight of all subgroups in the CRS group was significantly decreased (P<0.05); immobility time during tail suspension and forced swimming was significantly increased (P<0.05); and sugar preference rate and the total distance traveled and frequency of rearing behavior in the open field were significantly decreased (P< 0.05). Within the CRS group, compared to that of the young subgroup, the immobility time during tail suspension and forced swimming in the old subgroup was significantly increased (P<0.05); the sugar preference rate was significantly decreased (P<0.05); and the frequency of rearing behavior in the open field was significantly decreased (P<0.05). Conclusion: With normal aging, the younger the mice, the more likely they were to show behaviors of despair; the older the mice, the more severe were their behaviors of anxiety. With stress-related aging, the older the mice, the more serious was their depressive-like and anxiety-like behavior, especially that of anhedonia caused by impairment of the reward function.