Tsai L-L, Tsai Y-C
Department of Psychology, National Chung-Cheng University, Chia-yi, Taiwan, ROC.
Int J Obes (Lond). 2007 Sep;31(9):1368-77. doi: 10.1038/sj.ijo.0803607. Epub 2007 Mar 13.
To examine whether scheduled forced wheel activity counteracts the increased body weight gain in rats undergoing chronic circadian desynchronization induced by repeated 12-h shifts in the light-dark cycle.
Four age- and body weight-matched groups of adult male F344 rats were subjected to 12-h intermittent forced wheel activity daily (2.2 km/day). Each group had the following schedule for 13 weeks: a fixed schedule of a daily 12:12-h light-dark cycle and activity training (WF); a fixed light-dark cycle and 12-h shifts twice a week in activity training (WS); 12-h shifts twice a week in the light-dark cycle and a fixed schedule of activity training (LSWF); and 12-h shifts twice a week in both the light-dark cycle and activity training (LSWS). Two additional age- and body weight-matched sedentary rat groups were selected from our database: one was maintained on a fixed light-dark cycle (LC) and the other was subjected to 12-h shifts twice a week in the light-dark cycle (LS).
The four rat groups that were exercised showed different response patterns of the daily body temperature rhythm to different combinations of forced activity and lighting schedules. Their food intake was more than that of the two sedentary rat groups, but their body weight was comparable with that of the LC rats and less than that of the LS rats during the forced activity period. The LSWS rats were heavier than the WF and WS rats in the first and second months of the experimental treatment, but their body weight was comparable with that of the WS and WF rats in the third month.
Forced activity was effective in reducing the body weight gain in chronic circadian desynchronization that was induced by repeated shifts in the light-dark cycle, although such an effect might become significant only after some time.
研究定时强制轮转活动是否能抵消因明暗周期反复 12 小时变化导致慢性昼夜节律失调的大鼠体重增加。
将四组年龄和体重匹配的成年雄性 F344 大鼠，每天进行 12 小时间歇性强制轮转活动（每天 2.2 千米）。每组按以下方案进行 13 周实验：固定的每日 12:12 小时明暗周期及活动训练（WF）；固定明暗周期，活动训练每周两次 12 小时轮班（WS）；明暗周期每周两次 12 小时轮班，固定活动训练方案（LSWF）；明暗周期和活动训练均每周两次 12 小时轮班（LSWS）。从我们的数据库中选取另外两组年龄和体重匹配的久坐大鼠：一组维持固定明暗周期（LC），另一组明暗周期每周两次 12 小时轮班（LS）。
四组运动大鼠对强制活动和光照方案的不同组合，表现出不同的每日体温节律反应模式。它们的食物摄入量比两组久坐大鼠多，但在强制活动期间，它们的体重与 LC 组大鼠相当，且低于 LS 组大鼠。在实验治疗的第一个月和第二个月，LSWS 组大鼠比 WF 组和 WS 组大鼠重，但在第三个月，它们的体重与 WS 组和 WF 组大鼠相当。
强制活动能有效减轻因明暗周期反复变化导致的慢性昼夜节律失调大鼠的体重增加，尽管这种效果可能要经过一段时间才会显著。
