Herzog E D, Takahashi J S, Block G D
NSF Center for Biological Timing, University of Virginia, Charlottesville 22903, USA.
Nat Neurosci. 1998 Dec;1(8):708-13. doi: 10.1038/3708.
The suprachiasmatic nucleus (SCN) is the master circadian pacemaker in mammals, and one molecular regulator of circadian rhythms is the Clock gene. Here we studied the discharge patterns of SCN neurons isolated from Clock mutant mice. Long-term, multielectrode recordings showed that heterozygous Clock mutant neurons have lengthened periods and that homozygous Clock neurons are arrhythmic, paralleling the effects on locomotor activity in the animal. In addition, cells in dispersals expressed a wider range of periods and phase relationships than cells in explants. These results suggest that the Clock gene is required for circadian rhythmicity in individual SCN cells and that a mechanism within the SCN synchronizes neurons and restricts the range of expressed circadian periods.
视交叉上核（SCN）是哺乳动物的主昼夜节律起搏器，昼夜节律的一种分子调节因子是Clock基因。在此，我们研究了从Clock突变小鼠分离出的SCN神经元的放电模式。长期的多电极记录显示，杂合Clock突变神经元的周期延长，而纯合Clock神经元无节律，这与对动物运动活动的影响相似。此外，分散培养的细胞比外植体中的细胞表现出更广泛的周期和相位关系范围。这些结果表明，Clock基因是单个SCN细胞昼夜节律性所必需的，并且SCN内的一种机制使神经元同步并限制了所表达的昼夜周期范围。
