Actions of Estrogen & Environmental Estrogens on Neurons

描述（由申请人提供）：拟议研究的广泛长期目标是了解 17β-雌二醇（雌激素；E2）和雌激素受体（ER）在发育中的神经系统中的功能，并确定环境雌激素在多大程度上影响这些功能。 E2 影响男性和女性大脑许多区域的发育和功能。因此，其他雌激素化合物可能会影响大脑的发育。环境雌激素，也称为“内分泌干扰物”，是一组可以模拟或拮抗 E2 正常作用的多种化合物。环境雌激素对发育中的神经系统的影响程度尚不清楚。拟议的实验采用新生大鼠小脑神经元和发育中小脑的原代培养物作为模型，将解决以下具体目标-具体目标 1：确定 E2 是否通过对 MAPK 信号转导的快速、非基因组作用来调节发育中小脑神经元的细胞信号传导；具体目标2：确定小脑神经元中雌激素反应基因的网络，其表达受E2调节；具体目标 3：确定代表性环境雌激素在多大程度上模拟或抑制 E2 对小脑神经元发育的影响。具体目标 1 和 2 测试了以下假设：E2 在发育中的神经元中通常通过快速调节 MAPK 信号传导的活性以及通过基因组 ER 介导的机制发挥作用，这些机制共同改变基因产物离散网络的表达。具体目标 3 将测试这样的假设：环境雌激素通过修改 MAPK 信号传导和基因组 ER 介导的机制来影响发育中的神经元，从而导致表达基因网络的改变。所有三个具体目标将通过使用激活状态特异性抗血清的实验来确定 E2 介导的信号传导途径，并通过 cDNA 阵列和 E2 响应基因表达的 RT-PCR 分析来解决。根据这些结果，我们将开发神经元“E2 特征 cDNA 阵列”并将其用于目标 3，以确定环境雌激素如何影响这些发育神经元中 E2 响应基因的表达。

DESCRIPTION (provided by applicant): The broad long-term goal of the proposed research is to understand the functions of 17beta-estradiol (estrogen; E2) and estrogen receptors (ERs) in the developing nervous system and to determine to what extent environmental estrogens influence these functions. E2 influences the development and function of many regions of the brain in both males and females. Thus, it is possible that other estrogenic compounds can impact development of the brain. Environmental estrogens, also known as "endocrine disrupters," are a diverse group of compounds that can mimic or antagonize the normal actions of E2. The extent to which environmental estrogens impact the developing nervous system is unclear. Proposed experiments employing primary cultures of neonatal rat cerebellar neurons and the developing cerebellum as models will address the following Specific Aims-Specific Aim 1: Determine whether E2 modulates cellular signaling in developing cerebellar neurons through rapid, non-genomic actions on MAPK signal transduction; Specific Aim 2: Determine the networks of estrogen responsive genes whose expression is modulated by E2 in cerebellar neurons; Specific Aim 3: Determine to what degree representative environmental estrogens mimic or inhibit the effects of E2 in developing cerebellar neurons. Specific Aims 1 & 2 test the hypothesis that E2 normally functions in developing neurons by rapidly modulating the activity of MAPK signaling, and also through genomic ER-mediated mechanisms which together, modify expression of discrete networks of gene products. Specific Aim 3 will test the hypothesis that environmental estrogens influence developing neurons by modifying both MAPK signaling and genomic ER-mediated mechanisms, which results in altered networks of expressed genes. All three Specific Aims will be addressed through experiments using activation-state specific antisera to determine E2-mediated signaling pathways and by cDNA array and RT -PCR analysis of E2-responsive gene expression. From these results a neuronal "E2-signature cDNA array" will be developed and used in Aim 3 to determine how environmental estrogens influence E2-responsive gene expression in these developing neurons.