Ebling F J, Cronin A S
School of Biomedical Sciences, University of Nottingham, Queens Medical Centre, UK.
Neuroreport. 2000 Nov 9;11(16):R23-33. doi: 10.1097/00001756-200011090-00002.
This brief review has highlighted some of the major advances in the last decade or so in understanding the central control of puberty. These include the discovery that GnRH-I neurons develop in the olfactory placode and migrate into the forebrain, the recognition that puberty is a reactivation of GnRH secretion, the identification of leptin as a metabolic signal which may permit puberty to occur, unraveling the molecular basis of the circadian clock which underlies photoperiodic control of puberty in seasonal species, the identification of the structure of pheromones in urine, and the discovery of other populations of GnRH neurons in mammals expressing the GnRH-II gene. Such advances generate further questions: what regulates the migratory pathways of GnRH neurons, and what controls axon outgrowth and targeting to the median eminence? What is the mechanism which causes GnRH secretion to decline between the neonatal and pubertal phase of development? How do leptin and other sensory inputs finally communicate to the GnRH neuron? How do GnRH neurons communicate with each other such that co-ordinated pulsatile release of GnRH occurs? What is the function of GnRH-II? Some of these issues may be better addressed using the transgenic technologies which allow the identification and thus the recording, sampling and observation of GnRH neurons in living tissue, but in order to understand how internal and external cues influence puberty it will also be important to study a variety of other mammalian models in which the relative importance of such inputs differs.
这篇简短的综述突出了过去十年左右在理解青春期中枢控制方面的一些主要进展。这些进展包括发现促性腺激素释放激素 - I（GnRH - I）神经元在嗅基板中发育并迁移到前脑；认识到青春期是GnRH分泌的重新激活；确定瘦素作为一种代谢信号，可能促使青春期发生；揭示昼夜节律钟的分子基础，其是季节性物种青春期光周期控制的基础；确定尿液中信息素的结构；以及在哺乳动物中发现表达GnRH - II基因的其他GnRH神经元群体。这些进展引发了进一步的问题：是什么调节GnRH神经元的迁移途径，以及是什么控制轴突生长和靶向正中隆起？在发育的新生儿期和青春期之间导致GnRH分泌下降的机制是什么？瘦素和其他感觉输入最终如何与GnRH神经元进行通信？GnRH神经元如何相互通信从而实现GnRH的协调脉冲式释放？GnRH - II的功能是什么？其中一些问题可能使用转基因技术能得到更好的解决，转基因技术可在活组织中识别并因此记录、采样和观察GnRH神经元，但为了理解内部和外部线索如何影响青春期，研究各种其他哺乳动物模型也很重要，在这些模型中此类输入的相对重要性有所不同。
