运动对慢性应激所致抑郁样老年大鼠行为异常及神经内分泌的影响

Effect of exercise on chronic stress-induced abnormal behaviors and neuroendocrine function in elderly depression-like rats

目的探讨运动对慢性不可预见温和应激(CUMS)抑郁老年大鼠行为学及血清皮质醇和促肾上腺皮质激素(ACTH)浓度的影响。方法 50只雄性老年SD大鼠随机分为对照组、CUMS组、低强度跑台运动训练(LITT)组、中等强度跑台运动训练(MITT)组、高强度跑台运动训练(HITT)组。采用CUMS加孤养复制老年大鼠抑郁模型。采用旷场实验得分和强迫游泳实验评价各组大鼠行为学改变,分别采用ELISA和放射免疫方法检测血清皮质醇、ACTH浓度。结果与对照组比较,CUMS组大鼠血清皮质醇和ACTH浓度增高(P<0.01);与CUMS组比较,LITT组、MITT组和HITT组大鼠水平运动和垂直运动增多、清理次数增加,中央格停留时间缩短,血清皮质醇和ACTH浓度降低(P<0.05,P<0.01)。结论 CUMS可使老年大鼠行为及内分泌发生异常改变,引起抑郁;适度的运动可调节CUMS引起的下丘脑-垂体-肾上腺轴功能亢进,具有抗抑郁及降低抑郁程度的作用。

Objective To study the effect of exercise on chronic unpredictable mild stress（CUMS）- induced abnormal behaviors and serum cortisol （CORT） and adrenocorticotropie hormone （ACTH） levels in elderly depression-like rats. Methods Fifty elderly male SD rats were randomly divided into control group, model group, low intensity treadmill training（LITT）group, medium intensity treadmill training （MITT） group, and high intensity treadmill training （HITT） group （ 10 in each group）. A rat depression model was induced by CUMS. Bahaviors of rats were assessed ac- cording to the open field test and forced swimming test scores. Serum CORT and ACTH levels in different groups were measured by RIA and ELISA,respectively. Results The body weight gain was slower,the horizontal and vertical exercise scores and the modified scores were significantly lower, the central retention time was significantly longer, the serum CORT and ACTH levels were significantly higher in CUMS group than in control group（P^0.01）. The horizontal and vertical exercise scores and the modified scores were significantly higher, the central retention time was significantly shorter, the serum CORT and ACTH levels were significantly lower in LITT,MITT and HITTgroups than in CUMS group（P〈0.05,P〈0.01）. Conclusion CUMS with an antide- pressive effect can lead to abnormal neuroendocrine function and behaviors as well as depression in elderly rats. Moderate exercise can regulate CUMS-induced hyperfunction of hypothalamus,hy- pophysis and adrenal gland axis.