Reorganization of the suprachiasmatic nucleus coding for day length
Reorganization of the suprachiasmatic nucleus coding for day length
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DOI：
10.1177/0748730408314572
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发表时间：
2008-04-01
影响因子：
3.5
通讯作者：
Ebihara, Shizufumi
中科院分区：
文献类型：
--
作者：
Naito, Emiko;Watanabe, Tsuyoshi;Ebihara, Shizufumi
在哺乳动物中，视交叉上核（SCN）作为昼夜节律起搏器，通过视网膜接收光信息，并在昼夜节律的夹带以及行为和生理功能的季节性反应中发挥作用。为了更好地了解 SCN 生理学中与光周期相关的变化，我们通过对 mPer1::luc 生物发光进行原位杂交和实时监测来分析小鼠 SCN 中的时钟基因表达。长光周期（LP）条件下，尾侧SCN期mPer1和Bma11的表达节律领先于头侧SCN期；此外，在中SCN内，腹外侧（VL）样细分的节律比背内侧（DM）样细分的节律提前。从中间 SCN 获得的整个冠状切片中的 mPer1::luc 节律在 LP 条件下表现出 2 个峰宽较宽的峰。对 SCN 的头侧、中部、尾侧和水平 SCN 的几个细分中的 mPer1::luc 节律进行成像分析，揭示了 LP 条件下 SCN 头侧半部的峰值时间存在广泛的区域差异。这些变化并不是由于单个 SCN 神经元节律波形的改变造成的。我们的结果表明，LP 条件会引起 SCN 吻端多个区域节律的相位变化；这导致整个 SCN 中出现不同的昼夜节律波形，对日长进行编码。
In mammals, the suprachiasmatic nucleus (SCN), the circadian pacemaker, receives light information via the retina and functions in the entrainment of circadian rhythms and in phasing the seasonal responses of behavioral and physiological functions. To better understand photoperiod-related alterations in the SCN physiology, we analyzed the clock gene expression in the mouse SCN by performing in situ hybridization and real-time monitoring of the mPer1::luc bioluminescence. Under long photoperiod ( LP) conditions, the expression rhythms of mPer1 and Bma11 in the caudal SCN phase-led those in the rostral SCN; further, within the middle SCN, the rhythms in the ventrolateral (VL)-like subdivision advanced compared with those in the dorsomedial (DM)-like subdivision. The mPer1::luc rhythms in the entire coronal slice obtained from the middle SCN exhibited 2 peaks with a wide peak width under LP conditions. Imaging analysis of the mPer1::luc rhythms in several subdivisions of the rostral, middle, caudal, and horizontal SCN revealed wide regional variations in the peak time in the rostral half of the SCN under LP conditions. These variations were not due to alterations in the waveform of a single SCN neuronal rhythm. Our results indicate that LP conditions induce phase changes in the rhythms in multiple regions in the rostral half of the SCN; this leads to different circadian waveforms in the entire SCN, coding for day length.