Morphological analyses about origins, neurochemical substances and target-specificily of neurons coming to the subfornical organ

应用顺行和逆行追踪技术结合免疫组织化学方法，研究穹窿下器（SFO）神经元的来源、神经化学物质和靶特异性。为进一步研究含多种神经化学物质的神经末梢的分布和靶成分奠定了基础。SFO内有胺能、胆碱能和肽能神经末梢。SFO内5-羟色胺、脑啡肽-8（mE 8）、甘丙肽（GAL）、神经降压素和促黄体生成素释放肽免疫阳性神经末梢与胞体和树突形成突触，并与血管和胶质细胞紧密接触。mE 8阳性投射起源于前背侧和前腹侧室周核、视前区和下丘脑室周区、正中视前核、下丘脑背内侧核和弓状核、臂旁内侧核和孤束核，GAL阳性投射起源于内侧视前核、内侧小细胞室旁核、下丘脑室周区、下丘脑背内侧核和弓状核; Bornbesin免疫反应阳性投射为内侧小细胞室旁核和延髓头端腹外侧区，神经肽Y免疫反应阳性投射为下丘脑弓状核、孤束核和延髓腹外侧区，胆碱能投射为内侧隔核和斜角带。从正中视前核到SFO的投射是巨大的。SFO神经元投射到室旁核是SFO的主要靶点之一，其与主要来源的神经终末（如正中视前核、臂旁外侧核和中缝核）之间的关系是十分有趣的。这是要解决的问题。

Origins, neurochemical substances and target-specificity of neurons coming to the subfornical organ(SFO) were investigated using anterograde and retrograde tracing technique combined with immunohistochemistry. Distribution and target elements of nerve terminals containing several neurochemical substances were investigated for the basis of the study. There were aminergic, cholinergic and peptidergic nerve terminals in the SFO. Serotonin-,Met-enkephalin-8(mE8)-,galanin(GAL)-,neurotensin- and luteinizing hormone-releasing hormone-immunoreactive nerve terminals made synapses with cell bodies and dendrites, and contacted closely with vessels and glial cells in the SFO. Origins of mE8-immunoreactive projections were the anterodorsal and anteroventral periventricular nuclei, preoptic and hypothalamic periventricular regions, median preoptic nucleus, hypothalamic dorsomedial and arcuate nuclei, medial parabrachial nucleus and solitary nucleus ; GAL-immunoreactive projections were the medial preoptic nucleus, medial parvocellular paraventricular nucleus, hypothalamic periventricular regions, hypothalamic dorsomedial and arcuate nuclei ; bornbesin-immunoreactive projections were the medial parvocellular paraventricular nucleus and rostral ventrolateral medulla ; neuropeptide Y-immunoreactive projections were the hypothalamic arcuate nucleus, solitary nucleus and ventrolateral medulla ; cholinergic projections were the medial septal nucleus and diagonal band. Projections to the SFO from the median preoptic nucleus were huge. They made synapses with cell bodies and dendrites, and contacted closely with vessels and glial cells.It is very interesting to clear the relationship between SFO neurons projecting to one of the main targets, the paraventricular nucleus and nerve terminals coming from main origins, such as the median preoptic nucleus, lateral parabrachial nucleus and raphe nuclei. This is the matter to be solved.