NICOTINIC RECEPTORS IN CEREBRAL CORTICAL DEVELOPMENT

大脑皮质发育中的烟碱受体

• 批准号: 6231388
• 负责人: ALLAN S SCHNEIDER
• 金额: $ 7.9万
• 依托单位: ALBANY MEDICAL COLLEGE
• 依托单位国家: 美国
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-04-01 至 2003-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6231388
• 关键词: acetylcholine; astrocytes; calcium flux; cell component structure /function; cerebral cortex; chemical kinetics; confocal scanning microscopy; developmental neurobiology; embryo /fetus; embryo /fetus drug adverse effect; gestational age; immunocytochemistry; laboratory mouse; neurogenesis; neurons; nicotinic receptors; oligodendroglia; pharmacology; protein localization; protein structure function; smoking; stimulant /agonist; tissue /cell culture; voltage /patch clamp

DESCRIPTION: (Adapted from the applicant's Description) There is an extensive literature showing that fetal nicotine exposure, due to maternal smoking, alters embryonic brain development and results in a variety of pathological effects in the neonate that fall under the heading of the "fetal nicotine syndrome". Although the mechanisms involved are not well understood, they are thought to be mediated in part by nicotinic acetylcholine receptors in the fetal brain. Yet neither the existence of functional nicotinic receptors in early fetal mammalian brain nor their role in development are well established. The investigators have obtained preliminary evidence that functional nicotinic receptors are expressed on mouse cerebral cortical cells at early embryonic ages when the cortex consists mainly of dividing stem and progenitor cells. Initial results show that nicotinic agonist activation of these receptors evokes characteristic electrophysiological responses and cytosolic Ca++ signals in the E10 cells. These early findings now open up an interesting set of questions concerning the role nicotinic receptors play in early cortical development and how chronic fetal nicotine exposure may alter such development. Before one can address these long term issues, however, it is first necessary to resolve the more focused issues concerning the acquisition, properties, and cellular localization of functional nicotinic receptors in the developing cerebral cortex. Thus, the investigators' specific aims are to answer the following two questions: at what stages of embryonic development do mouse cerebral cortical cells acquire functional nicotinic Ach receptors? And which subtypes of nicotinic receptors are present in the mouse cortex at different stages of development and which neural cells types are they on? Isolated mouse cerebral cortical cells derived from E10, E13, and E18 embryos will be used. Receptor functionality will be assessed by nicotinic agonist-induced Ca++ signaling and patchclamp electrophysiology. Receptor subtypes will be identified by pharmacological and kinetic analysis of functional responses. Immunocytochemistry will also be used to identify receptor subtypes and the different neural cell types they may be on. The results of this project will lay the groundwork for further exploration of the role of nicotinic receptors in normal development and that of nicotine as a neuroteratogen.

描述：（改编自申请人的描述）有一个 大量文献表明，由于母亲的原因，胎儿接触尼古丁 吸烟会改变胚胎大脑发育并导致多种疾病 对新生儿的病理影响属于“胎儿 尼古丁综合症”。尽管所涉及的机制尚不清楚， 它们被认为部分由烟碱乙酰胆碱受体介导 在胎儿的大脑中。 然而，功能性烟碱的存在并不存在。 早期胎儿哺乳动物大脑中的受体及其在发育中的作用尚不明确 建立良好。 调查人员已获得初步证据表明 功能性烟碱受体在小鼠大脑皮层细胞上表达 在胚胎早期，皮质主要由分裂茎和 祖细胞。 初步结果表明烟碱激动剂激活 这些受体引起特有的电生理反应 E10 细胞中的胞质 Ca++ 信号。 这些早期发现现在开辟了一个新的领域 关于烟碱受体在烟碱受体中的作用的一系列有趣的问题 早期皮质发育以及长期接触尼古丁可能如何改变胎儿 这样的发展。 然而，在解决这些长期问题之前， 首先要解决比较集中的问题 功能性烟碱的获取、特性和细胞定位 发育中的大脑皮层中的受体。 因此，调查人员的 具体目标是回答以下两个问题：在什么阶段 胚胎发育过程中小鼠大脑皮层细胞是否获得功能 烟碱乙酰胆碱受体？ 烟碱受体有哪些亚型 存在于不同发育阶段的小鼠皮质中， 它们的神经细胞类型是什么？ 分离的小鼠大脑皮层细胞 将使用源自 E10、E13 和 E18 胚胎的胚胎。 受体功能 将通过烟碱激动剂诱导的 Ca++ 信号传导和膜片钳进行评估 电生理学。 受体亚型将通过药理学鉴定 和功能反应的动力学分析。 免疫细胞化学也将 用于识别受体亚型及其不同的神经细胞类型 可能已开启。 该项目的成果将为进一步的研究奠定基础 探索烟碱受体在正常发育中的作用 尼古丁作为神经致畸剂。