【作者】 肖明；

【导师】 丁炯； 王鹤鸣； 韩群颖；

【作者基本信息】 南京医科大学 ， 解剖学与组织胚胎学， 2001， 硕士

【摘要】 目的：通过对大鼠下丘脑、脑干内与心血管活动调节相关核团中一氧化氮合酶（NOS）阳性神经元的分布、纤维投射以及与催产素、β-内啡肽共存关系的研究，为进一步阐明一氧化氮（NO）在中枢神经系统心血管活动中的调节作用与以NO为中介的下丘脑垂体-神经体液调节机制，提供了较详细的形态学资料；并为进一步探索与完善以NO——气体神经递质为核心的新型神经内分泌调节网络提供了的基础性研究依据。方法与材料：通过黄递酶组织化学方法观察NOS阳性神经元在大鼠下丘脑与脑干内的分布，并结合辣根过氧化物酶逆行追踪技术观察室旁核、臂旁核、兰斑和孤束核等心血管调节核团中NOS阳性神经元的细胞构筑与纤维投射；利用黄递酶组织化学结合催产素免疫组织化学双标技术观察大鼠第三脑室NOS阳性触液神经元的分布及其与催产素的共存关系；结合β-内啡肽免疫组织化学双标技术，观察脑干内NOS与β-内啡肽的共存关系；并利用直流电损毁顺行溃变法结合辣根过氧化物酶逆行追踪技术在电镜水平上观察了大鼠孤束核-臂旁核-中央杏仁核间接纤维投射。结果：1．下丘脑NOS阳性神经元可分两种类型，即小细胞型NOS阳性神经元与大细胞型NOS阳性神经元。前者主要分布于下丘脑小细胞神经分泌神经元系统；后者主要集中分布于下丘脑视上核与室旁核。在正中隆起的外带、内带均可见到大量NOS阳性纤维，分别与垂体前、后叶相连。2．下丘脑室旁核内小细胞型NOS阳性神经元，占少部分，散在分布于室旁核小细胞部与背内侧帽；大细胞型NOS阳性神经元，占大部分，分别集中分布于前连合核、内侧室旁核、外侧室旁核、室旁核后亚核，其阳性纤维主要形成室旁垂体束投射至垂体后叶；其中内 南京医科大学硕士学位论文侧室旁核与外侧室旁核的部分NOS 阳性神经纤维可投射至下丘脑邻近区域，如中央杏仁核等边缘系统；而小细胞部、背内侧帽与室旁核后亚核的部分NOS 阳性纤维可投射至臂旁核等脑干相关核团。3．第三脑室的顶部、背侧部、腹侧部与底部均存在NOS阳性触液神经元。各部NOS阳性触液神经元的形态、分布以及与催产素的共存率存有差异。其中背侧部NOS阳性触液神经元的分布范围、数目以及与催产素的共存率要高于腹侧部，其NOS阳性纤维主要参与室旁垂体束，投射至垂体后叶；腹侧部的 NOS阳性纤维多终止于第三脑室底腹侧壁与正中隆起室管膜层。4．NOS 阳性神经元广泛分布于脑干各相关核团内，并与卜内啡肽部分共存；兰斑、臂旁核和孤束核的各亚核内NOS阳性神经元与阳性纤维的分布均存有差异；部分NOS阳性纤维可投射至中央杏仁核。5．孤束核－臂旁核冲央杏仁核之间存有间接纤维联系，分布于臂旁核内孤束核的轴突终末，可与投射至中央杏仁核的神经元及其它结构形成十分密切的并列关系。结论：＊OS阳性神经元广泛分布于大鼠脑内心血管调节核团，并具有相互纤维投射，提示 NO参与中枢。。血管调节活动；下丘脑、第三脑室与垂体均有NOS阳性神经元与纤维分布，提示＊O参与下丘脑－垂体神经体液调节过程；脑内的突触并列结构可能是NO通过自分泌与旁分泌方式发挥有效生物信使与信息分子作用的结构基础。更多还原

【Abstract】 Objcetive: To provide the anatomic data for further understanding of the role of nitric oxide (NO) in the central visceral and cardiovascular regulation and the mechanism of hypothalamus-hypophysis neurohumoral regulation mediated by NO , We studied the distribution of nitric oxide synthase (NOS) positive neurons and the coexistence of NOS and oxytocin(OT)or f3-endorphin(j3-EOP), and projections in some nuclei of hypothalamus and brainstem which are involved in central visceral and cardiovascular regulation. All those results will give the basis material for exploration and perfection of the new neuroendocrine network , in which nitric oxide-gaseous neuromediator plays an important role. Materials and methods : The distribution of NOS positive neurons in the nuclei of hypothalamus and brainstem was observed by NADPH-diaphorase histochemitry method. Cytoarchitecture and projections of NOS neurons in the paraventricular nucleus(PVN), the parabrachi al nucleus(PBN) ,the locus coeruleus nucleus (LC), the SoLitary nucleus (SoL) were investigated by combining with the horseradish peroxidase(HRP) retrograde tracing techniques, The coexistence of NOS with OT or -EOP was studied in the third ventricle or brainstem by combining NADPH-diaphorase histochemical technique with immunocytochemical methods in the same section . By combining the anterograde degeneration method caused by electrolytic lesions with HRP retrograde tracing techniques, We also observed the SoL-PBN-CAN indirect connection pathway in the rat on the electron microscopic level Results: 1. NOS positive neurons in the hypothalamus could be divided into two types: microcellular NOS positive neurons and magnocellular NOS positive neurons. The former were almost in the region of microcellular neurosecretory neurons, the latter were in the region of magnocellular 8 neurons, especially in the PVN and supraoptic nucleus . A large number of NOS positive fibres were aggregate at the external and medial lamina of the median eminence (ME) respectively connecting with the anterior or posterior lobe of the pituitary 2.In the PVN, the microcellular NOS positive neurons were in the minority , scattering over the parvocellular division and dorsomedial cap . The majority of magnocellular NOS positive neurons were aggregate at four magnocellular subneclei of PVN : anterior commissural nucleus(AC) , medial paraventricular nucleus , lateral paraventricular nucleus , and posterior subnucleus of the paraventricular nucleus (PvPO).Their NOS fibres projected to the posterior lobe of the pituitary gland. In the PVM and PVL,some NOS positive neurons projected to neighbors region of the limb system including the central nucleus of the amygdala (CAN) , while in the parvocellular division,the dorsomedial cap and PvPO , some NOS positive neurons were found projecting to the brainstem nuclei, such as parabrachial nucleus.3. NOS positive cerebrospinal fluid-contacting neurons(NOS-CSFCN) cound be found in all the four walls of the third ventricle. In each wall, the morphology and distribution of NOS-CSFCN and the ratio of coexistence of NOS/OT were different . The range of the distri更多还原