慢性疲劳发生过程中小鼠血清皮质酮的动态变化

目的通过观察小鼠血清皮质酮（corticosterone,CorT）的动态变化,探讨在亚健康状态中慢性疲劳的发生发展机制。方法昆明小鼠120只,完全随机分为10组,分别为：正常对照0、4、9、16、23d组和模型：0、4、9、16、23d组,每组12只。正常组小鼠自由饮食,模型各组小鼠置于水深为0.5cm的塑料盒内18h/d。负7%体重力竭游泳以检测疲劳程度,放射免疫法检测血清CorT含量。结果正常组小鼠在实验过程中体重有上升的趋势但差异无统计学意义（P〉0.05）;游泳时间逐渐下降,从第9天起差异有统计学意义（P〈0.05）;皮质醇无明显变化（P〉0.05）。模型组小鼠随着造模时间的延长体重显著减轻（P〈0.01）;力竭游泳时间显著下降,第4天起差异有统计学意义（P〈0.01）;血清CorT第4天开始升高,第16天达分泌高峰（P〈0.01）,随后逐渐下降,但各时间点与正常对照组比较仍显著升高（P〈0.05）。结论随着小鼠疲劳的加重,血清CorT呈现出先升高后降低的动态变化,提示肾上腺皮质代偿性功能亢进后有功能衰退的趋势,可能是慢性疲劳发生发展及转归机制之一。

Effect of Chronic Fatigue on the Changes of Serum Corticosterone

Objective To study effect of chronic fatigue on the dynamic change of the serum corticosterone （CorT）. Methods 120 KM mice were randomly divided into control and experimental group. The mice in these 2 groups were further subdivided into 5 groups （n=12） for the subsequent study at day-0,4,9,16 and 23. Mice in the experimental groups were kept in plastic boxes filled with water to a height of 0.5 cm for 18 hours a day. Weight-loaded forced swimming test was used to evaluate the extent of fatigue. Radioimmuno-assay was used to determine the level of serum CorT. Results For the mice in the control group,there was a tendency of increase in the body weight,but the difference was not significant difference （P0.05）. A progressively decreased in the swimming time was observed at day-9 （P0.05） but the level of serum CorT was not chenage （P0.05）. For the mice in the experimental group,the body weight was time-dependently increased （P0.01）. Reduction of swimming time was observed at day-4 （P0.01） and the level of serum CorT was also significantly increased at day-4 （P0.01）. The level of CorT reached maximum at day-16 （P0.01） and then gradually decreased. But the the level of CorT was still higher than the control group （P0.05）. Conclusion The change in the level of serum CorT was associated with chronic fatigue. Hypocortisolism followed by compensatory hypercorticalism might be a part of mechanism of chronic fatigue.