Osiel S, Golombek D A, Ralph M R
Department of Psychology, University of Toronto, Ontario, Canada.
Physiol Behav. 1998 Aug;65(1):123-31. doi: 10.1016/s0031-9384(98)00140-1.
Locomotor activity in rodents is restricted temporally by the animal' s circadian system. The relative stability of both the species-specific pattern and the amount of locomotor activity per cycle suggested that this behavior may be regulated by conservative mechanisms. In these experiments, the wheel-running behavior of golden hamsters carrying the circadian period mutation, tau, was analyzed in animals housed in a 24-h light:dark cycle (LD) and in constant dark (DD) conditions to determine which aspects of this behavior were conserved. In DD, apart from the change in period which defines the mutation, no main effects of allele combination were found in either average amount of activity, activity profile, or length of the activity phase. In LD, wild-type behavior did not differ from that in DD; however, heterozygous mutants exhibited early onsets of activity, significant fragmentation of both activity and rest, an increase in the duration of the active phase, and an overall decrease in the amount of activity. Despite these differences, the total amount of time spent on the wheel in LD or DD was the same for all environment/genotype combinations. The data show that a conservative mechanism that may influence daily patterns of locomotor behavior is related more to a drive to perform the behavior than the quantity or timing of the behavior itself.
啮齿动物的运动活动在时间上受到动物昼夜节律系统的限制。每个周期中物种特异性模式和运动活动量的相对稳定性表明，这种行为可能受保守机制的调节。在这些实验中，对携带昼夜节律周期突变tau的金黄地鼠在24小时光照：黑暗周期（LD）和持续黑暗（DD）条件下饲养的动物的轮转行为进行了分析，以确定这种行为的哪些方面是保守的。在DD条件下，除了定义突变的周期变化外，在活动的平均量、活动模式或活动阶段的长度方面均未发现等位基因组合的主要影响。在LD条件下，野生型行为与DD条件下的行为没有差异；然而，杂合突变体表现出活动开始时间提前、活动和休息明显碎片化、活动阶段持续时间增加以及活动总量总体减少。尽管存在这些差异，但对于所有环境/基因型组合，在LD或DD条件下在轮子上花费的总时间是相同的。数据表明，一种可能影响运动行为日常模式的保守机制更多地与行为驱动力有关，而不是行为本身的数量或时间。
