Neuronal Reguration of the Hypothalamic-hypophysial Axis Immunohistochemistry

我们研究了大鼠下丘脑-垂体系统的神经元调节机制。我们的第一个目的是找出下丘脑含垂体营养激素神经元和含有神经活性物质的神经元之间的突触关联，这些神经活性物质已知会影响含垂体营养激素神经元。因此，我们开发了一种双重免疫标记技术，结合下丘脑内手术横切神经元通路或纤维束逆行示踪，同时检测突触前和突触后成分中的不同神经活性物质。此外，我们还利用胚胎下丘脑组织的器官培养和移植技术来探索下丘脑垂体营养神经元的起源。首先，我们研究了含促性腺激素（GaRH）的神经元的起源。它们起源于鼻部，依次迁移到末端神经节，并进一步迁移到内表面。最后到达中隔-视前区，从中延伸轴突投射到发育中的中隆起，释放激素GnRH到门静脉。这表明分泌性垂体营养GnRH神经元来源于感觉GnRH神经元。为了了解这种迁移是如何通过培养或移植到成年大鼠的第三脑室中与下丘脑内侧基底部或大脑皮层相连的鼻基板引起的。具有长轴突的分泌神经元与毛细血管结合形成中隆起样结构，仅在与内侧基底下丘脑共移植的移植物中出现。中隔-预分化区GnRH神经元受精确核含p物质神经元的突触调节。此外，我们还发现下丘脑含有神经肽y的神经元的发育及其与室旁核中含有抗利尿激素的神经元的突触关联。此外，我们已经证明了在副细胞室旁核中含有生长抑素的神经元和含有促肾上腺皮质激素释放激素的神经元之间的相互调节关系。少

We examined the neuronal regulation mechanisms of the hypothalamic-hypophysial system in rats. Our first aim was to find out synaptic associations between hypothalamic hypophysiotrophic hormone-containing neurons and neurons containing neuroactive substances which are known to affect the hypophysiotrophic hormone-containing neurons. Hence we developed a double immunolabeling technique to detect simultaneously different neuroactive substances in pre-and postsynaptic components in combining with intrahypothalamic surgery to transect neuronal pathways or with retrograde tracing of fiber tracts. Additionally we pursued the origins of hypothalamic hypophysiotrophic neurons by using organ culture and transplantation techniques of embryonal hypothalamic tissues. First of all we examined the origin of gonadotrophic hormone roleasing hormono (GaRH)-containing neurons. They derived from the nasal placode : migrating sequentially to the terminal ganglion and further to the internal surface of the … More telencephalon vesicles ; and reaching finally the septo-preoptic area, wherefrom, they extend axonal projections to the developing median eminence to release hormonal GnRH to the portal capiilaries. This suggests that secretory hypophysiotrophic GnRH neurons derive from sensory GnRH neurons. To know what this migration is induced by the nasal placode with the medial basal hypothalamus or cerebral cortex was cultured or transplanted into the third ventricle of adult rats. Secretory neurons with long axonal processes conjugated with blood capillaries to form median eminence like-structures appeared only in the grafts co-transplanted with the medial basal hypothalamus. GnRH neurons in the septo-prepotic area were synaptically regulated by substance P-containing neurons localized in the acurate nucleus. Further we have shown the development of hypothalamic neuropeptide Y-containing neurons and their synaptic associations with vasopressin-containing neurons in the paraventricular nucleus. Furthermore, we have demonstrated the teciprocal regultaory relations between somatostatin-containing neurons and corticotrophin releasing hormone-containing neurons in the parvocellular paraventricular nucleus. Less