Localization of a Suprachiasmatic Nucleus Subregion Regulating Locomotor Rhythmicity
Localization of a Suprachiasmatic Nucleus Subregion Regulating Locomotor Rhythmicity
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DOI：
10.1523/jneurosci.19-13-05574.1999
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发表时间：
1999-07
期刊：
影响因子：
--
通讯作者：
J. LeSauter;R. Silver;Rae Silver
中科院分区：
文献类型：
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作者：
J. LeSauter;R. Silver;Rae Silver
下丘脑两侧对称的视交叉上核（SCN）是哺乳动物生物钟控制昼夜节律的场所。先前的研究表明，SCN的所有区域是等电位的，因为部分消融后的昼夜节律性是持续的，只要保留约25%的核。与这些结果相反，我们发现，动物轴承部分病变的SCN幸免于亚区划定的细胞含有钙结合蛋白-D28 K（CaBP），持续的昼夜运动节律。此外，节律的强度与备用CaBP细胞的数量之间存在相关性。部分病变破坏了这一地区，但幸免于其他车厢的SCN导致丧失节律性。接下来的研究表明，移植含有CaBP细胞的半SCN移植物恢复了SCN损伤的宿主动物的运动节律，而含有SCN组织但缺乏该亚核细胞的移植物未能恢复节律性。最后，移植物中CaBP阳性细胞的数量与恢复节律的强度之间存在相关性。两者合计，结果表明，在该地区的CaBP亚核的起搏器是必要的和足够的运动节律的控制和SCN是功能异质性。
The bilaterally symmetrical suprachiasmatic nuclei (SCN) of the hypothalamus are the loci of the mammalian clock controlling circadian rhythms. Previous studies suggested that all regions of the SCN are equipotential as circadian rhythmicity is sustained after partial ablation, as long as ∼25% of the nuclei are spared. In contrast to these results, we found that animals bearing partial lesions of the SCN that spared the subregion delimited by cells containing the calcium-binding protein calbindin-D28K (CaBP), sustained circadian locomotor rhythms. Furthermore, there was a correlation between the strength of the rhythm and the number of spared CaBP cells. Partial lesions that destroyed this region but spared other compartments of the SCN resulted in loss of rhythmicity. The next study indicates that transplants of half-SCN grafts that contain CaBP cells restore locomotor rhythms in SCN-lesioned host animals, whereas transplants containing SCN tissue but lacking cells of this subnucleus fail to restore rhythmicity. Finally, there was a correlation between the number of CaBP-positive cells in the graft and the strength of the restored rhythm. Taken together, the results indicate that pacemakers in the region of the CaBP subnucleus are necessary and sufficient for the control of locomotor rhythmicity and that the SCN is functionally heterogeneous.