Gene Expression and Drug Targets in the Rostromedial Tegmentum

描述(申请人提供)：2009年，我们和其他人最近发现了一个以前被忽视的大脑区域，即旋转内侧被盖核(RMTg)。这些神经元通过向多巴胺神经元的密集投射，以及来自外侧缰核、杏仁核延长区和其他与影响和动机有关的区域的主要输入，在厌恶学习、行为和成瘾中发挥关键作用。RMTg神经元是许多(尽管不是所有)与恐惧、焦虑、疼痛和戒毒相关的厌恶行为所必需的。尽管最近关于RMTG的解剖学、生理学和行为学特征的知识迅速增长，但这些神经元的遗传特性几乎完全未知。目前尚不清楚它们含有什么神经递质(除了GABA)，也不知道它们是否具有受体、摄取转运体或其他可以选择性地操纵其Firin速率的药物靶点。此外，RMTg区域在Nissl染色上缺乏清晰的边界，如果没有神经示踪剂或立即早期基因诱导，就无法可视化，这些方法往往与其他实验范例不兼容。因此，在该区域的基础科学和临床研究方面的进一步进展需要开发分子工具和药物靶点，以选择性地识别和操纵这些神经元。为了满足这些需求，我们建议首先使用荧光激活细胞分类(FACS)将这些神经元从周围结构中分离出来，然后对全基因组表达阵列进行分析，最后通过原位杂交来确认候选基因的表达模式，从而检测RMTg基因的表达。我们希望这一结果将填补我们对这种新兴大脑结构的知识的主要空白，同时也为临床前和临床使用提供新的工具。 与公共健康相关：2009年，我们和其他人发现了一个以前被忽视的大脑区域，被盖旋转内侧核(RMTg)，它为中脑多巴胺神经元提供密集的GABA神经支配，在厌恶学习和行为中发挥关键作用。尽管有相当大的兴趣，但由于缺乏针对这些神经元的分子和遗传工具，对这一重要区域的进一步研究受到阻碍。通过提供这些工具，拟议的研究可以极大地加快RMTG的临床前和临床研究。

DESCRIPTION (provided by applicant): In 2009, we and others recently identified a previously overlooked brain region, the rostromedial tegmental nucleus (RMTg). These neurons play key roles in aversive learning, behavior, and addiction, via their dense projections to dopamine neurons, and major inputs from the lateral habenula, extended amygdala, and other regions implicated in affect and motivation. RMTg neurons are critically required for many (though not all) aversive behaviors related to fear, anxiety, pain, and drug withdrawal. Despite the rapid recent growth of knowledge regarding RMTg anatomic, physiological, and behavioral characteristics, the genetic properties of these neurons are almost entirely unknown. It is unknown what neurotransmitters (besides GABA) they contain, nor whether they exhibit receptors, uptake transporters, or other drug targets that could selectively manipulate their firin rates. Furthermore, the RMTg region lacks sharp boundaries on Nissl stains, and cannot be visualized without neural tracers or immediate early gene induction, methods often incompatible with other experimental paradigms. Hence, further progress in basic science and clinical studies of this region requires development of molecular tools and drug targets that selectively identify and manipulate these neurons. To meet these needs, we propose to examine RMTg gene expression by first using fluorescence activated cell sorting (FACS) to isolate these neurons from surrounding structures, followed by analysis on whole-genome expression arrays, and concluding with in situ hybridization to confirm expression patterns of candidate genes. We expect the results to fill in major gaps in our knowledge of this emerging brain structure, while also producing new tools for preclinical and clinical use. PUBLIC HEALTH RELEVANCE: In 2009, we and others identified a previously overlooked brain region, the rostromedial tegmental nucleus (RMTg), which provides dense GABA innervations of midbrain dopamine neurons, and plays key roles in aversive learning and behavior. Despite considerable interest, further research on this vital region is hampered by the lack of molecular and genetic tools specific to these neurons. By providing such tools, the proposed study could greatly accelerate pre-clinical and clinical studies of the RMTg.