ENVIRONMENTAL REGULATION OF SYMPATHOADRENAL PHENOTYPIC EXPRESSION

该项目的主要目的是提供一个更清晰的了解 细胞群体获得它们的分化过程。 神经化学特性 待研究的细胞群是两个 交感肾上腺系统的组成部分，神经元从 椎旁交感神经节和肾上腺嗜铬细胞。 这些细胞从神经嵴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， 多巴胺、去甲肾上腺素、肾上腺素、脑啡肽、生长抑素、血管活性 肠多肽神经肽Y和可能的血清素。 环境因素已被证明可以决定和调节 获得和表达的几种神经递质的性质， 哺乳动物交感肾上腺系统 然而，我们小组最近的研究结果 表明分化和获得生物化学物质的过程 交感神经元的特性在鸟类和哺乳动物之间不同。 为了 为了更好地了解我们将使用的生化分化过程 鸟类模型 我们建议（1）表征和定量 单胺在鸡胚发育过程中的表达 孵化后阶段，并将其与我们的神经肽发育数据进行比较（2） 在体内和体外测试几种环境因素对 神经活性物质的表达，包括单胺和 神经肽 放射免疫测定将用于定量神经肽的量， 高效液相色谱-电化学 检测将用于鉴定和定量单胺的量， 动物和文化。 免疫细胞化学和神经化学 技术将用于识别和量化细胞的数量， 表现出不同的表型 结果应该会导致一个更好的 了解内分泌或神经系统的细胞 分化为表达特定神经递质的细胞， 神经肽或肽激素。

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.