Lateralization of Circadian Pacemaker Output: Activation of Left- and Right-Sided Luteinizing Hormone-Releasing Hormone Neurons Involves a Neural Rather Than a Humoral Pathway
Lateralization of Circadian Pacemaker Output: Activation of Left- and Right-Sided Luteinizing Hormone-Releasing Hormone Neurons Involves a Neural Rather Than a Humoral Pathway
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昼夜节律起搏器输出的偏侧化：左侧和右侧黄体生成激素释放激素神经元的激活涉及神经途径而不是体液途径
作者：
H. O. de la Iglesia;Jennifer Meyer;W. Schwartz
金黄地鼠的运动活动和黄体生成素（LH）的分泌在视交叉上核（SCN）有一个共同的昼夜节律起搏点，但这些节律似乎没有共同的SCN输出通路。运动被认为是由体液因素驱动的，而LH分泌可能取决于特定的同侧神经传出从SCN到视前区含LH释放激素（LHRH）的神经元。在本文中，我们提供了第一个功能的证据，这样的传出神经系统完整的仓鼠利用一种现象称为“分裂”在恒定的光，其中约12小时（约12小时）自发活动发作反映了反相振荡的左侧和右侧的双边配对SCN。在卵巢切除，雌激素治疗（OVX + E2）的雌性仓鼠，分裂也被称为包括约12小时LH分泌高峰。在这里，我们发现，行为“分裂”OVX + E2女性表现出显着的左，右不对称的免疫反应c-Fos的表达在SCN和激活LHRH神经元，与LHRH+/c-Fos+双标记细胞的百分比约5倍高对应的一侧SCN具有较高的c-Fos免疫反应。我们的研究结果表明，分裂涉及LHRH神经元的左侧和右侧交替刺激;在这种情况下，下丘脑神经内分泌的功能活动反映了SCN基因表达的内在侧到侧差异。生殖活动的昼夜节律调节依赖于侧化的、点对点的轴突投射，而不是扩散性因素。
Locomotor activity and luteinizing hormone (LH) secretion in golden hamsters share a common circadian pacemaker in the suprachiasmatic nucleus (SCN), but the rhythms do not seem to share a common output pathway from the SCN. Locomotion is believed to be driven by humoral factor(s), whereas LH secretion may depend on specific ipsilateral neural efferents from the SCN to LH releasing hormone (LHRH)-containing neurons in the preoptic area. In this paper we provide the first functional evidence for such efferents in neurologically intact hamsters by exploiting a phenomenon known as “splitting” in constant light, in which circa-12 hr (approximately 12 hr) locomotor activity bouts reflect an antiphase oscillation of the left and right sides of the bilaterally paired SCN. In ovariectomized, estrogen-treated (OVX + E2) female hamsters, splitting is also known to include circa-12 hr LH secretory surges. Here we show that behaviorally “split” OVX + E2 females exhibit a marked left-right asymmetry in immunoreactive c-Fos expression in both SCN and activated LHRH neurons, with the percentage of LHRH+/c-Fos+ double-labeled cells approximately fivefold higher on the side corresponding to the side of the SCN with higher c-Fos immunoreactivity. Our results suggest that splitting involves alternating left- and right-sided stimulation of LHRH neurons; under such circumstances, the functional activity of the neuroendocrine hypothalamus mirrors intrinsic side-to-side differences in SCN gene expression. The circadian regulation of reproductive activity depends on lateralized, point-to-point axonal projections rather than on diffusible factors.
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叙利亚仓鼠黄体生成素释放激素神经元中 Fos 的昼夜表达。
影响因子：
3.6
作者：
Doan,A;Urbanski,HF
通讯作者：
Urbanski,HF
影响因子：
4.8
作者：
Meyer-Bernstein, EL;Jetton, AE;Bittman, EL
通讯作者：
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DOI：
10.1210/endo.140.2.6538
发表时间：
1999
期刊：
Endocrinology.
影响因子：
--
作者：
Lucas,RJ;Stirland,JA;Darrow,JM;Menaker,M;Loudon,AS
通讯作者：
Loudon,AS
影响因子：
56.9
作者：
de la Iglesia, HO;Meyer, J;Schwartz, WJ
通讯作者：
Schwartz, WJ