EMBRYONIC DEVELOPMENT OF EPINERGIC NEURONS IN BRAIN

表观能神经元表达合成肾上腺皮质激素所需的特定酶 肾上腺素。拟议的研究将调查胚胎和 大鼠脑干和脑干内表胺能神经元的生后分化 脊髓和下丘脑的肾上腺素能纤维。此外，有可能 激素对表型表型标志物发展的影响 在体内和体外进行研究。免疫细胞化学，放射自显影， 高效液相色谱、放射酶分析和组织 培养将结合起来，以提供形态和生化 表碱能分化的描述。具体地说，建议的 研究试图1)定义神经发生之间的时间关系 在神经管和神经嵴中的表型表达 导数，2)研究暂时性神经递质现象 在脑中的表达，3)描述了脑内肾上腺素能纤维的发育 脊髓和下丘脑，4)中枢和外周肾上腺素能 细胞对糖皮质激素可能的调节，5)阐明 糖皮质激素对肾上腺素能发育的可能经胎盘作用 在胎儿的大脑和脊髓中，6)研究 表型能神经元肽能表型，7)研究因素 长期给药对表神经元体外发育的影响 延髓胚性外植体培养。 这些研究涉及发育生物学的基本问题和 神经科学，涉及细胞决定的过程， 特异性和差异性。对涉及的因素进行澄清 神经递质在脑内的表达和发育及其可能的作用 作为细胞外影响的激素，在未来可能会导致 对发育中神经元环境变化的位置的理解 会产生异常的发展。反过来，这可能有助于 了解人类的出生缺陷并最终进行治疗 对涉及神经元分化的过程的操纵。

Epinergic neurons express specific enzymes required for the synthesis of epinephrine. The proposed studies will investigate the embryonic and postnatal differentiation of epinergic neurons in the rat brainstem and epinergic fibers in spinal cord and hypothalamus. In addition, possible hormonal influences on the development of epinergic phenotypic markers will be studied in vivo and in vitro. Immunocytochemistry, autoradiography, high-performance liquid chromatography, radioenzymatic assay and tissue culture will be combined to provide morphological and biochemical descriptions of epinergic differentiation. Specifically, the proposed studies seek to 1) define the temporal relationships between neurogenesis and epinergic phenotypic expression in neural tube and neural crest derivatives, 2) investigate the phenomenon of transient neurotransmitter expression in the brain, 3) describe the development of epinergic fibers in spinal cord and hypothalamus, 4) compare central to peripheral epinergic cells with respect to possible regulation by glucocorticoids, 5) elucidate possible transplacental effects of glucocorticoids on epinergic development in the fetal brain and spinal cord, 6) investigate expression of peptidergic phenotypes in epinergic neurons, and 7) study factors which influence the in vitro development of epinergic neurons in long-term explant cultures of embryonic medulla oblongata. These studies address fundamental issues in developmental biology and neuroscience concerning the processes involved in cell determination, specificity and differentiation. Elucidation of factors involved in neurotransmitter expression and development in brain and the possible role of hormones as extracellular influences, may, in the future, lead to an understanding of loci where changes in the milieu of the developing neuron produces aberrant development. In turn, this may contribute to an understanding of birth defects in the human and ultimately to therapeutic manipulation of processes involved in neuronal differentiation.