Sharma V K, Chidambaram R, Subbaraj R, Chandrashekaran M K
Chronobiology Laboratory, Evolutionary and Organismal Biology Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, P. O. Box. 6436, Bangalore 560 064, Karnataka, India.
Physiol Behav. 2000;70(1-2):81-7. doi: 10.1016/s0031-9384(00)00217-1.
The effect of restricted feeding (RF) cycles on the circadian locomotor activity rhythm was studied in the nocturnal field mouse Mus booduga. Mice were presented with a 2-h meal schedule every 24 h in continuous darkness (DD), in continuous light (LL), and in a light-dark (LD) cycle. Additionally, in DD, two groups of mice were subjected to RF cycles of periodicities 22 (T22) and 26 h (T26), respectively, in order to assess the limits of entrainment. The T22 and T26 RF cycles failed to produce any entrainment of the locomotor activity rhythm, whereas some of the animals that had a free-running period (tau) close to 24 h showed stable entrainment or "relative coordination" to daily (T24) RF cycle. In LD, the locomotor activity rhythm phase advanced under the influence of the daily RF cycle when the food presentation preceded the light to dark (L to D) transition by 5-6 h. However, when the timing of food presented in the RF cycle coincided with the L to D transition, locomotor activity rhythm dissociated into two components. Some of the mice whose locomotor activity rhythm disappeared in LL showed prominent meal-AA. These results suggest that RF modifies the expression of the light-entrainable pacemaker (LEP) directly and also that in the absence of the expression of the LEP, RF can induce meal-AA.
在夜行性田鼠（Mus booduga）中研究了限时进食（RF）周期对昼夜运动活动节律的影响。在持续黑暗（DD）、持续光照（LL）和明暗（LD）循环条件下，每隔24小时给小鼠安排2小时的进食时间。此外，在DD条件下，两组小鼠分别接受周期为22小时（T22）和26小时（T26）的RF周期，以评估昼夜节律的调节极限。T22和T26的RF周期未能使运动活动节律产生任何调节，而一些自由运行周期（tau）接近24小时的动物对每日（T24）RF周期表现出稳定的调节或“相对协调”。在LD条件下，当食物呈现先于从明到暗（L到D）的转变5 - 6小时时，运动活动节律在每日RF周期的影响下提前。然而，当RF周期中食物呈现的时间与L到D的转变一致时，运动活动节律分解为两个部分。一些在LL中运动活动节律消失的小鼠表现出明显的进餐活动。这些结果表明，RF直接改变了光可调节起搏器（LEP）的表达，并且在没有LEP表达的情况下，RF可以诱导进餐活动。
