Herbison A E
Laboratory of Neuroendocrinology, Babraham Institute, Cambridge, UK.
Rev Reprod. 1997 Jan;2(1):1-6. doi: 10.1530/ror.0.0020001.
The GnRH cells represent the final output neurones of an integrated neuronal network used by the brain to generate pulsatile LH secretion from the pituitary gland. Changes in LH secretion profile throughout the ovarian cycle, including the preovulatory LH surge, result principally from alterations in the output of this GnRH network and it has been a key goal of many neurobiologists to elucidate the components and nature of this network. This review documents recent progress in understanding the role of noradrenaline within the GnRH network and highlights and explains its 'enabling' or permissive characteristics. Network behaviour analysis suggests that noradrenaline should be considered as a permissive agent promoting high output states of the GnRH network. On the basis of recent molecular and neuroanatomical data, it is proposed that oestrogen influences brainstem noradrenergic neurones specifically within the nucleus tractus solitarius to facilitate synaptic transmission within the GnRH network. In this manner, noradrenaline is likely to play a role in bringing about the increased GnRH messenger RNA expression and secretion necessary for ovulation.
促性腺激素释放激素（GnRH）细胞是大脑用于产生垂体促黄体生成素（LH）脉冲式分泌的整合神经元网络的最终输出神经元。整个卵巢周期中LH分泌模式的变化，包括排卵前LH峰，主要源于该GnRH网络输出的改变，阐明该网络的组成和性质一直是许多神经生物学家的关键目标。本综述记录了在理解去甲肾上腺素在GnRH网络中的作用方面的最新进展，并突出和解释了其“促成”或允许性特征。网络行为分析表明，应将去甲肾上腺素视为促进GnRH网络高输出状态的允许性因子。基于最近的分子和神经解剖学数据，有人提出雌激素特别影响孤束核内的脑干去甲肾上腺素能神经元，以促进GnRH网络内的突触传递。通过这种方式，去甲肾上腺素可能在导致排卵所需的GnRH信使核糖核酸表达和分泌增加中发挥作用。
