FUNCTIONAL ORGANIZATION OF THE NERVUS TERMINALIS

终神经(NT)是一种有神经节的脑神经。 连接大脑和周围的嗅觉结构。这个 在大多数脊椎动物中都发现了NT，包括成年人类 而且，尽管用各种技术反复研究，但 NT仍然是唯一具有这种功能的脑神经 在人类或任何物种中都是完全未知的。基于 神经在NT内的联系和细胞形态 神经节，解剖学家提出，神经可能服务于 感觉和自主神经功能相结合。也许是其中一个 最近关于NT最重要的发现是，一些 神经中的神经元含有高水平的黄体生成素- 释放激素(LHRH)免疫反应性。其中一些 LHRH免疫反应细胞投射到参与 繁殖和一些似乎与 血管。促性腺激素释放激素在NT中的表达 神经元和神经的中枢和外周连接 导致一些研究人员认为NT可能是 对信息素化学敏感，参与生殖 在鱼类和哺乳动物中的功能，可能是通过释放LHRH 直接进入血液。然而，目前还没有 电生理证据表明化学感受器或 NT的神经内分泌功能，目前尚不清楚 NT神经节的电路与这些建议兼容 功能。 生理组织和形态组织的研究 将为更多的知情人士提供基础计划 NT功能的研究。弹性支链将用在这些 研究，因为只有在这些动物中，NT才是分开的 从大脑直接接触到电生理 实验。这里提出的实验包括：1) 电生理、药理和形态 对NT神经节细胞的研究，这将提供关于 生理上的传入和/或传出投射 特征细胞；2)结合电生理学、染料填充和 免疫细胞化学将研究肽的功能(S) 包含细胞，包括这样的细胞 构成神经的传入或传出成分；3) 所有实验数据的整合将提供第一个 NT神经节神经元回路的连贯图像， 包括元素之间的突触相互作用 神经节。

The nervus terminalis (NT) is a ganglionated cranial nerve which connects the brain and the peripheral olfactory structures. The NT has been found in most vertebrates, including adult humans and, although studied repeatedly with a variety of techniques, the NT remains the only cranial nerve for which the function is completely unknown in humans or in any species. Based on the connections of the nerve and the morphology of cells in the NT ganglion, anatomists have suggested that the nerve may serve a combined sensory and autonomic function. Perhaps one of the most significant recent findings concerning the NT is that some neurons in the nerve contain high levels of luteinizing hormone- releasing hormone (LHRH) immunoreactivity. Some of these LHRH-immunoreactive cells project to brain areas involved with reproduction and some appear to have direct connections with blood vessels. The presence of LHRH-immunoreactivity in the NT neurons and the central and peripheral connections of the nerve has led some researchers to suggest that the NT may be chemosensitive to pheromones and involved in reproductive functions in fish and mammals, possibly by releasing LHRH directly into the blood. However, there has been no electrophysiological evidence for either a chemosensory or a neuroendocrine function for the NT and it is not known if the circuitry of the NT ganglion is compatible with these suggested functions. Investigation of the physiological and morphological organization of the NT ganglion will provide a ground-plan for a more informed investigation of NT function. Elasmobranchs will be used in these studies, because it is only in these animals that the NT is separate from the brain and directly accessible for electrophysiological experiments. Experiments proposed here include: 1) electrophysiological, pharmacological and morphological investigations of NT ganglion cells, which will provide data on the afferent and/or efferent projections of physiologically characterized cells; 2) combined electrophysiology, dye-fills and immunocytochemistry will investigate the function(s) of peptide containing cells, including the possibility that such cells constitute the afferent or efferent component of the nerve; 3) integration of data from all experiments will provide the first coherent picture of the neuronal circuitry of the NT ganglion, including the synaptic interactions between elements within the ganglion.