Theodosis D T, Montagnese C, Rodriguez F, Vincent J D, Poulain D A
Nature. 1986;322(6081):738-40. doi: 10.1038/322738a0.
The hypothalamo-neurohypophysial system offers a unique example in the adult mammalian central nervous system (CNS) of a functional and structural plasticity related to a physiological state. During lactation, oxytocin neurones evolve a synchronized electrical activation which permits pulsatile hormone release at milk ejection. At the same time, in the supraoptic (SON) and paraventricular nuclei, glial coverage of neurones diminishes, so that large portions of their surface membrane become directly juxtaposed; synaptic remodelling also associates pairs of neurones through the formation of common presynaptic terminals. These structural changes, reversible after weaning, affect exclusively oxytocinergic neurones and could facilitate their synchronized electrical activity. As several observations suggest that oxytocin itself is released centrally, we have examined the effect of prolonged intracerebroventricular infusions of oxytocin on the structure of the SON of non-lactating animals. We report here that the peptide indeed engenders the structural reorganization characteristic of the oxytocin system when it is physiologically activated. Similar infusion of vasopressin has no effect. Our observations thus demonstrate that a central neuropeptide can induce anatomical changes in the adult CNS, and suggest that oxytocin can regulate its own release by contributing to the dramatic restructuring of the nuclei containing the neurones responsible for its secretion.
下丘脑 - 神经垂体系统在成年哺乳动物中枢神经系统（CNS）中提供了一个与生理状态相关的功能和结构可塑性的独特例子。在哺乳期，催产素神经元会发生同步电激活，这使得在乳汁排出时激素能呈脉冲式释放。同时，在视上核（SON）和室旁核中，神经元的胶质细胞覆盖减少，从而使它们的大部分表面膜直接并列；突触重塑还通过形成共同的突触前终末将成对的神经元联系起来。这些断奶后可逆的结构变化仅影响催产素能神经元，并可能促进它们的同步电活动。由于一些观察结果表明催产素本身也在中枢释放，我们研究了长时间脑室内输注催产素对非泌乳动物视上核结构的影响。我们在此报告，当该肽在生理上被激活时，确实会引发催产素系统特有的结构重组。类似地输注抗利尿激素则没有效果。因此，我们的观察结果表明，一种中枢神经肽可以在成年中枢神经系统中诱导解剖学变化，并表明催产素可以通过促成含有负责其分泌的神经元的核团的显著重组来调节自身的释放。
