Siebert U, Wollnik F
Department of Biology, University of Konstanz, Germany.
Physiol Behav. 1993 Jun;53(6):1145-50. doi: 10.1016/0031-9384(93)90371-l.
Wheel-running activity of LEW/Ztm rats is characterized by a multimodal pattern consisting of two activity bouts about 3-5 h apart. In this study we investigated the development of activity rhythms in LEW rats born and raised under three different photoperiods (LD 18:6, LD 12:12, and LD 6:18). Wheel-running activity was measured for 6 weeks in LD and for another 6 weeks in constant darkness (DD). The length of the photoperiod influenced the phase relationship between the two activity bouts only during the first week after weaning. Then, the characteristic activity pattern was established independently of the length of the photoperiod. However, development under long photoperiods (LD 18:6) resulted in a temporary increase in the level of activity and a significant shortening of the free-running period under DD. These results indicate that the multimodal activity pattern displayed by LEW rats is controlled by separate activity oscillators that establish their unique phase relationship early during development.
LEW/Ztm大鼠的轮转活动具有多模式特征，由两个间隔约3 - 5小时的活动期组成。在本研究中，我们调查了在三种不同光周期（LD 18:6、LD 12:12和LD 6:18）下出生并饲养的LEW大鼠活动节律的发展情况。在光照-黑暗周期（LD）下测量轮转活动6周，然后在持续黑暗（DD）中再测量6周。光周期的长度仅在断奶后的第一周影响两个活动期之间的相位关系。然后，特征性的活动模式独立于光周期的长度而建立。然而，在长光周期（LD 18:6）下发育导致活动水平暂时增加，并且在DD下自由运行周期显著缩短。这些结果表明，LEW大鼠表现出的多模式活动模式由独立的活动振荡器控制，这些振荡器在发育早期就建立了它们独特的相位关系。
