Vascular Interactions of Estrogen Receptor GPR30 and the Renin-Angiotensin System

描述（由申请人提供）：我的职业目标是获得独立的NIH资助，并建立一个成功的研究项目，阐明GPR30受体在雌激素心血管效应中的作用。我成为一名独立研究者的潜力不仅包括科学动力和成功，美国心脏协会博士后奖学金证明了这一点，而且还包括对科学界的承诺，我在ASPET等科学组织的工作表明了这一点。这个过渡奖将使我获得额外的技术和批判性思维技能，这是作为一名成功的独立调查员所必需的。维克森林大学的高血压和血管研究中心为这项培训提供了一个最佳的环境，因为有大量的可用资源和学院氛围。这些资源不仅包括科学设备和核心设施，还包括教学、跨部门合作和专业发展的机会。我的导师马克·查佩尔博士有着出色的资助记录，广泛的发表记录，在科学界备受尊敬。他出色的指导能力将确保我成为一名成功的独立调查员。绝经前女性的许多心血管疾病发病率较低，包括高血压。因为这种保护在绝经后急剧下降，我们知道雌激素至少在这些有益作用中起了部分作用。有两种已知的雌激素受体亚型介导这种激素的基因组作用；然而，尚不清楚新发现的g蛋白偶联受体30 （GPR30）是否与雌激素的心血管作用有关。我们实验室使用mRen2。Lewis大鼠是一种独特的血管紧张素ii依赖性、雌激素敏感性和盐敏感性高血压模型，它适当地反映了绝经后妇女的高血压和盐敏感性。我们之前的数据显示，在切除卵巢的女性体内给予选择性GPR30激动剂G-1可显著降低血压，改变肾素-血管紧张素系统成分的血管基因表达，并减少血管紧张素ii诱导的血管收缩。这些结果表明GPR30可以抵消激活的肾素-血管紧张素系统。G-1还能诱导内皮不依赖型血管松弛，提示受体定位于血管平滑肌。我们假设GPR30通过对抗Ang II在血管平滑肌细胞中的作用而发挥有益的心血管作用。将雌激素在GPR30上的作用与其核雌激素受体介导的作用分离开来，可能有助于阐明目前围绕激素替代疗法的争议。该提案将采用综合方法，利用体外细胞培养系统，离体分离抗性血管制备，以及同源mRen2的体内分析。刘易斯高血压动物。在指导的一年中，我将确定GPR30在肠系膜平滑肌细胞中的激活是否通过改变Ca2+储存破坏对血管紧张素II的反应。对于独立期，我概述了三个目标：(1)确定性别和雌激素状态是否调节mRen2菌株血管GPR30和RAS成分的表达；(2)确定血管平滑肌细胞中GPR30的激活是否改变肾素-血管紧张素系统组分的表达及其相关功能；(3)评估高盐是否改变血管GPR30表达，以及G-1是否通过改变肾血管功能改善盐敏感性。这些研究将建立血管GPR30表达的调控，并评估其与肾素-血管紧张素系统的急性和慢性相互作用。这个过渡奖将为我提供额外的指导，以实现未来作为一名独立研究者的成功，并允许我研究一个新的研究领域，这是临床相关的。关于GPR30在雌激素对心血管影响中的作用的信息可能会缓解目前关于绝经后妇女激素替代的争议。为了维持一个独立的实验室，并为科学界做出重大贡献，我承诺维持NIH等机构的财政支持。

DESCRIPTION (provided by applicant): My career goal is to secure independent NIH funding and establish a successful research program elucidating the role of the GPR30 receptor in the cardiovascular effects of estrogen. My potential to become an independent investigator not only includes scientific drive and success, evidenced by an American Heart Association postdoctoral fellowship, but also commitment to the scientific community, indicated by my work in scientific organizations such as ASPET. This transition award will allow me to acquire the additional techniques and critical thinking skills necessary for success as an independent investigator. The Hypertension and Vascular Research Center at Wake Forest University presents an optimal environment for this training due to the numerous resources available and the collegial atmosphere. These resources include not only scientific equipment and core facilities but also opportunities for teaching, interdepartmental collaboration, and professional development. My mentor, Dr. Mark Chappell, has an excellent funding record, an extensive publication record, and is well-respected among the scientific community. His excellent mentoring skills will ensure my success as an independent investigator. Premenopausal females have a lower incidence of many cardiovascular diseases, including hypertension. Because this protection steeply declines after menopause, we know that estrogen is at least partially responsible for these beneficial effects. There are two known estrogen receptor subtypes that mediate the genomic actions of this hormone; however, it is not known whether the newly discovered G-protein coupled receptor 30 (GPR30) contributes to estrogen's cardiovascular effects. Our laboratory utilizes the mRen2.Lewis rat, a unique angiotensin II-dependent, estrogen-sensitive, and salt-sensitive hypertensive model which appropriately reflects the higher blood pressure and salt-sensitivity seen in postmenopausal women. Our previous data show that in vivo administration of the selective GPR30 agonist G-1 in ovariectomized females significantly reduces blood pressure, alters vascular gene expression of renin-angiotensin system components, and reduces angiotensin II-induced vasoconstriction. These results suggest that GPR30 counteracts an activated renin-angiotensin system. G-1 also induces endothelium-independent vasorelaxation, suggesting receptor localization in vascular smooth muscle. We hypothesize that GPR30 exerts beneficial cardiovascular effects by opposing the actions of Ang II in vascular smooth muscle cells. Separating the actions of estrogen at GPR30 from those mediated by its nuclear estrogen receptors may elucidate the current controversy surrounding hormone replacement therapy. The proposal will take a comprehensive approach utilizing an in vitro cell culture system, an ex vivo isolated resistance vessel preparation, and in vivo analysis of the congenic mRen2.Lewis hypertensive animal. During the mentored year, I will determine whether GPR30 activation in mesenteric smooth muscle cells disrupts the response to angiotensin II by altering Ca2+ storage. For the independent phase, I have outlined three aims: (1) establish whether gender and estrogen status regulate vascular GPR30 and RAS component expression in the mRen2 strain.; (2) determine whether GPR30 activation in vascular smooth muscle cells alters the expression of renin-angiotensin system components and their associated functions; and (3) Assess whether high salt alters vascular GPR30 expression and whether G-1 ameliorates salt-sensitivity by altering renovascular function. These studies will establish the regulation of vascular GPR30 expression and assess its acute and chronic interaction with the renin-angiotensin system. This transition award will provide me the additional mentoring necessary to achieve future success as an independent investigator and will allow me to study a novel area of research which is clinically relevant. Information on the role of GPR30 in the cardiovascular effects of estrogen may alleviate the current controversy on hormone replacement in postmenopausal women. I am committed to maintaining financial support from institutes such as the NIH in order to sustain an independent laboratory and make significant contributions to the scientific community. PUBLIC HEALTH RELEVANCE: Premenopausal females have a lower incidence of many cardiovascular diseases, including hypertension. Because this protection steeply declines after menopause, we know that estrogen has beneficial effects. There are two known estrogen receptors that mediate the long-term actions of this hormone; however, it is not known whether the newly discovered G-protein coupled receptor 30 (GPR30) contributes to estrogen's protective effects. Information on the role of GPR30 in the beneficial effects of estrogen may alleviate the current controversy on hormone replacement in postmenopausal women.