P7: BRAIN-TARGETED ACE2 OVEREXPRESSION AND BLOOD PRESSURE REGULATION

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 肾素-血管紧张素系统(RAS)是健康和疾病中心血管和肾功能的主要调节因子。通常的假设是血管紧张素-II(Ang-II)是这一系统的主要参与者。血管紧张素转换酶2(ACE2)是RAS的一个新成员，已在与心血管功能相关的器官和组织(如心脏、肾脏、血管)中被发现，并似乎是缓冲Ang-II过量的反向调节途径的一部分。我们最近在大脑中发现了参与血压中枢调节的区域的ACE2蛋白，并表明它受到RAS的其他成分的调节。这些观察结果增加了ACE2在生物活性多肽产生中的作用，为进一步探索面对正常和病理生理状态的大脑提供了理论基础。在这个方案中，我们假设ACE2是RAS中大脑的一个功能元件，它的下调导致高血压的发生。利用我们在生理基因组学(一门研究基因操作的生理后果的科学)方面的专业知识，结合对心血管功能和清醒小鼠的最新记录和分析，我们建议调查短暂和慢性ACE2过度表达对血压中枢调节和高血压发展的影响。利用脑靶向ACE2过表达和腺病毒介导的ACE2转基因的基因工程小鼠，我们将解决以下问题： 1)正常小鼠脑内血管紧张素转换酶2过度表达的功能后果是什么？ 2)小鼠脑内ACE2的慢性过表达是预防还是延缓高血压的发生？ 3)ACE2过表达是否影响Ang-II信号通路？ 我们相信，这些独特的模型和基因靶向方法将使我们能够确定体内中枢ACE2在高血压中的生理作用。 血管紧张素转换酶2在高血压中作用的证据可能导致新疗法的开发，以及更好地利用现有疗法治疗高血压和其他心血管疾病。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The renin-angiotensin system (RAS) is a major regulation of cardiovascular (CV) and renal function in health and disease. The common assumption was that angiotensin-II (ANG-II) served as the main actor of this system. A new member of the RAS, ACE2 (angiotensin converting enzyme type 2) has been identified in organs and tissues related to CV function (e.g. heart, kidney, vessels) and appears to be part of a counter-regulatory pathway buffering the excess of Ang-II. We recently identified the ACE2 protein in the brain in regions involved in the central regulation of blood pressure and showed that it was regulated by other components of the RAS. These observations added to the role of ACE2 in the generation of biologically active peptides supply a rationale for further explorations in the brain in the face of normal and pathophysiological states. In this proposal, we hypothesize that ACE2 is a functional element of the brain in RAS and its down-regulation leads to the development of hypertension. Taking advantage of our expertise in physiological genomics, a science that studies the physiological consequences of gene manipulation, combined to state of the art recording and analysis of CV function and conscious mice, we propose to investigate the effects of transient and chronic ACE2 overexpression on the central regulation of blood pressure and the development of hypertension. Using genetically-engineered mice with brain-targeted ACE2 overexpression and adenovirus-mediated delivery of an ACE2 transgene, we will address the following questions: 1) What are the functional consequences of overexpression of ACE2 in the brain of normal mice? 2) Does chronic ACE2 overexpression in mouse brain prevent or delay the development of hypertension? 3) Does ACE2 overexpression affect Ang-II signaling pathways? We believe that these unique models and gene-targeting approaches will allow us to determine the physiological role of central ACE2 in vivo in hypertension. Evidence of a role of ACE2 in hypertension could lead to the development of new therapeutics as well as a better utilization of existing therapeutics for the treatment of hypertension and other CV diseases.