The mineralocorticoid receptor as a potential bridge between traumatic stress and increased alcohol consumption

项目摘要 酒精使用障碍（AUD）是一个严重的公共卫生问题，影响大约1510万美国成年人， 或11%的人在过去一个月内饮酒。有几个风险因素可以增加 发展酒精使用障碍的风险，例如共病创伤后应激障碍（PTSD）， 导致AUD风险增加3倍。关于创伤后应激障碍如何影响 与AUD相关，部分原因是动物模型相对较新。在我们的实验室里，我们发现 捕食者气味（PO）2，5-二氢-2，4，5-三甲基噻唑啉（TMT）对PO产生持久的反应性 暴露背景，PO背景再暴露后焦虑样行为升高，以及酒精自我增加。 PO暴露后一个月内给药，表明PO暴露可能是一种有前途的模型， 研究创伤后应激障碍和澳元的共病。为了为理解这些之间的重叠奠定基础， 该项目将重点关注压力和酒精文献中的一个新兴目标， 盐皮质激素受体（MR）。研究表明，MR介导了情境恐惧的发展 条件反射，杏仁核中的MR表达在束缚应激后下调，两种模型 与PTSD有关。此外，最近的研究表明，较低的MR基因表达与 在有饮酒史的大鼠和猴子中发现更多的饮酒和焦虑行为。目的 其中1项拟议工作旨在了解PO暴露后MR是否失调，以及 调节障碍是酒精自我管理、寻求和重新启动自我的基础。 局通过分析血浆醛固酮、MR蛋白和基因来评估MR失调 分别通过ELISA、western blot和qRT-PCR检测PO暴露大鼠的表达。为了分析 MR在饮酒中的功能作用，PO暴露的大鼠将被训练以自我施用酒精并接受 在自我给药期之前或在寻求/重新开始自我给药之前， 禁欲后的管理会议。这项工作的目的2旨在了解MR信号是否是必不可少的 PO暴露的长期影响的发展，并且其中脑区域MR介导神经元的 对PO暴露的反应。MR拮抗剂螺内酯将在捕食者气味出现之前给予大鼠 暴露和大鼠的焦虑样行为，酒精自我给药， 如我们的初步研究中所述，寻求和重新开始自我给药，或牺牲90分钟 随后检测即刻早期基因c-Fos的脑区域表达。总之，完成这些 目的是将MR建立为创伤应激和饮酒升级之间的潜在桥梁， 这些知识可以用于进一步研究这些共病情况并开发新药 治疗。

PROJECT SUMMARY Alcohol use disorder (AUD) is a serious public health concern, affecting approximately 15.1 million US adults, or 11% of those that consumed alcohol within the past month. There are several risk factors that can increase the risk of developing an alcohol use disorder, such as comorbid post-traumatic stress disorder (PTSD) which attributes a 3-fold increase in risk of developing an AUD. There is a significant gap in knowledge of how PTSD relates to AUDs, in part because animal models for this are relatively new. In our lab we find that exposure to the predator odor (PO) 2,5-dihydro-2,4,5-trimethylthiazoline (TMT) produces lasting reactivity to the PO exposure context, elevated anxiety-like behavior following PO context re-exposure, and increased alcohol self- administration over a month after PO exposure, suggesting that PO exposure may be a promising model to study comorbid PTSD and AUD. In order to lay groundwork for understanding the overlap between these disorders, this project will focus on an emerging target in both the stress and alcohol literature, the mineralocorticoid receptor (MR). It has been shown that MR mediates development of contextual fear conditioning, and MR expression in the amygdala is downregulated following restraint stress, two models relevant to PTSD. Additionally, recent studies have shown that lower MR gene expression is associated with greater alcohol drinking and anxiety behaviors in rats and monkeys with a history of alcohol consumption. Aim 1 of the proposed work seeks to understand if MR is dysregulated following PO exposure, and if this dysregulation underlies the elevations in alcohol self-administration, seeking, and re-initiation of self- administration. MR dysregulation will be assessed by analyzing plasma aldosterone, and MR protein and gene expression of PO exposed rats by ELISA, western blot, and qRT-PCR respectively. To assay changes in the functional role of MR in alcohol drinking, PO exposed rats will be trained to self-administer alcohol and receive the MR antagonist spironolactone prior to a self-administration session or prior to a seeking/re-initiation of self- administration session following abstinence. Aim 2 of this work seeks to understand if MR signaling is essential to the development of the long term effects of PO exposure, and in which brain regions MR mediates neuronal response to PO exposure. The MR antagonist spironolactone will be administered to rats prior to predator odor exposure and rats will either be assayed for the elevations in anxiety-like behavior, alcohol self-administration, seeking, and re-initiation of self-administration as described in our preliminary studies, or sacrificed 90 minutes later to examine brain regional expression of the immediate early gene c-Fos. Together, completion of these aims will establish the MR as a potential bridge between traumatic stress and escalations in alcohol drinking, and that knowledge can be used to further research these comorbid conditions and develop novel drug treatments.