Hundahl Christian Ansgar, Allen Gregg C, Nyengaard Jens Randel, Dewilde Sylvia, Carter Bruce Douglas, Kelsen Jesper, Hay-Schmidt Anders
Department of Neuroscience and Pharmacology, The Panum Institute, University of Copenhagen, Copenhagen, Denmark.
Neuroendocrinology. 2008;88(3):173-82. doi: 10.1159/000129698. Epub 2008 May 2.
Neuroglobin (Ngb) is a neuronal hemeprotein similar to myoglobin and hemoglobin and shares their capability for oxygen binding. It has thus been proposed that Ngb acts as an oxygen reservoir or combats reactive oxygen species. In the present study, we investigated the Ngb expression pattern in the rat brain using immunohistochemistry, in situ hybridization, and quantitative real-time PCR (qRT-PCR). This revealed the interesting finding that Ngb expression is restricted to a few neurone populations, many of which are involved in the sleep-wake cycle, circadian regulation or food regulation. In the forebrain we found intense Ngb expression in neurones in the piriform cortex, the central and medial amygdala, the medial preoptic area, the suprachiasmatic nucleus (SCN), the hypothalamic paraventricular nucleus, the perifornical nucleus, the lateral hypothalamus. Within the mid- and hindbrain Ngb expressing neurones were found in the laterodorsal tegmental nucleus, the pedunculo pontine tegmental nucleus, the locus coeruleus, and the lateral parabrachial nucleus. In the medulla oblongata Ngb expressing neurones were found in the nucleus of the solitary tract. The qRT-PCR data showed a diurnal variation of Ngb mRNA in the SCN, having a peak in the day time (light-period) and nadir during night (dark-period).
神经球蛋白（Ngb）是一种神经元血红素蛋白，与肌红蛋白和血红蛋白相似，具有与它们相同的氧结合能力。因此，有人提出Ngb可作为氧储备或对抗活性氧。在本研究中，我们使用免疫组织化学、原位杂交和定量实时PCR（qRT-PCR）研究了大鼠脑中Ngb的表达模式。这揭示了一个有趣的发现，即Ngb的表达仅限于少数神经元群体，其中许多神经元参与睡眠-觉醒周期、昼夜节律调节或食物调节。在前脑中，我们发现梨状皮质、中央杏仁核和内侧杏仁核、内侧视前区、视交叉上核（SCN）、下丘脑室旁核、穹窿周核、下丘脑外侧区的神经元中有强烈的Ngb表达。在中脑和后脑内，在外侧背侧被盖核、脑桥脚被盖核、蓝斑和外侧臂旁核中发现了表达Ngb的神经元。在延髓中，在孤束核中发现了表达Ngb的神经元。qRT-PCR数据显示SCN中Ngb mRNA存在昼夜变化，在白天（光照期）达到峰值，在夜间（黑暗期）降至最低点。
