ENVIRONMENTAL REGULATION OF SYMPATHOADRENAL PHENOTYPIC EXPRESSION

这个项目的主要目的是让人们更清楚地了解 细胞群体获得其自身基因的分化过程 神经化学性质。要研究的细胞群有两个 交感-肾上腺系统的组成部分，来自 椎旁交感神经节和肾上腺嗜铬细胞。 这些细胞与神经脊中常见的前体细胞分化为 神经元和嗜铬细胞合成神经活性物质，如 多巴胺、去甲肾上腺素、肾上腺素、脑啡肽、生长抑素、血管活性物质 肠多肽、神经肽Y，可能还有5-羟色胺。 环境因素已被证明决定和调节 大鼠脑内几种神经递质特性的获得和表达 哺乳动物的交感-肾上腺系统。然而，我们小组最近的结果 表明生物化学的分化和获得的过程 交感神经元的特征在鸟类和哺乳动物中是不同的。按顺序 为了更好地理解生化分化过程，我们将使用 鸟类模型。我们建议(1)表征和量化 单胺类物质在鸡胚胎发育过程中的表达 孵化后阶段，并与我们的神经肽发育数据进行比较(2) 体内外几种环境因素对血管内皮细胞生长的影响 神经活性物质的表达，包括单胺类和 神经肽。 放射免疫分析将用于量化神经肽和 高效液相色谱与电化学联用 检测将被用来识别和量化单胺类物质的数量 在动物和文化中。免疫细胞化学和神经化学 将使用技术来识别和量化细胞的数量 表现出不同的表型。结果应该会带来更好的 了解来自内分泌或神经系统的细胞如何 分化成表达特定神经递质的细胞， 神经肽或多肽激素。

The main aim of this project is to provide a clearer understanding of the differentiation process by which cell populations acquire their neurochemical properties. The cell populations to be studied are two components of the sympathoadrenal system, the neurons from the paravertebral sympathetic ganglia and the adrenal gland chromaffin cells. These cells differentiate from common precursors in the neural crest into neurons and chromaffin cells that synthesize neuroactive substances such as dopamine, norepinephrine, epinephrine, enkephalin, somatostatin, vasoactive intestinal polypeptide neuropeptide Y and possibly serotonin. Environmental factors have been shown to determine and modulate the acquisition and expression of several neurotransmitter properties in the mammalian sympathoadrenal system. However, recent results from our group indicate that the process of differentiation and acquisition of biochemical traits by sympathetic neurons differs between birds and mammals. In order to better understand the biochemical differentiation process we will use the avian model. We propose to (1) characterize and quantitate the expression of monoamines in the developing chicken through embryonic to post-hatched stages and compare it to our neuropeptide development data (2) test the effect of several environmental factors in vivo and in vitro on the expression of neuroactive substances, both monoamines and neuropeptides. Radioimmunoassays will be used to quantify the amount of neuropeptides and high performance liquid chromatography together with electrochemical detection will be used to identify and quantify the amount of monoamines in the animal and in cultures. Immunocytochemical and neurochemical techniques will be used to identify and quantify the number of cells showing different phenotypes. The results should lead to a better understanding of how cells from the endocrine or nervous systems differentiate into cells expressing specific neurotransmitters, neuropeptides or peptide hormones.