Sympathetic Vascular Regulation following Heat Stress in Young and Aged Humans

项目摘要/摘要 心血管疾病(CVD)是发达国家的主要死亡原因。随着年龄的增长 心血管疾病的一个主要风险因素，人类的平均寿命正在增加，心血管疾病预计将 达到前所未有的水平，并给医疗保健系统带来巨大负担。而这些 人口结构的变化是不可避免的，心血管疾病的发展是可以预防的。因为高血压 比任何其他可改变的风险因素导致更多的心血管疾病死亡，针对 血压的管理是预防这些发人深省的心血管疾病预测的关键 变成了现实。热疗，以热水浴和桑拿浴的形式，是一种古老的做法，它有 最近在治疗和预防心血管疾病方面得到了重视，因为经常使用桑拿与 降低了全因心血管疾病死亡的风险。就像锻炼一样，炎热的许多慢性益处 治疗可能是在恢复期进行的。例如，一次单次锻炼 促进血压持续下降，称为运动后低血压， 短暂地将升高的血压降至正常血压范围，并增强有益 运动训练中的心血管适应。同样，我们和其他人也展示了一个 单次热应激后健康和健康人群血压持续下降 患者群体。然而，这种后加热背后的神经血管机制 低血压的机会之窗是未知的，代表着知识上的关键差距。因此， 我们的目标是探索加温后低血压、压力感受性反射控制和交感血管。 年轻人和老年人全身热应激后的转导。我们假设 在无压力感受器反射的情况下，向下和向左的压力感受器反射重置可支持加温后低血压 在年轻人和老年人中交感神经血管转导的改变。此外，我们 假设血压下降和压力感受器反射重置的幅度是 在老年人中被夸大了。总的来说，这项工作提高了我们对适应性角色的理解 将热疗作为血液管理的一种治疗选择 心血管疾病的压力和预防。作为候选人，拉尔森女士完成了拟议中的研究，网址为 俄勒冈大学与她经验丰富的共同导师明森博士和哈里威尔博士一起，她将 获得临床试验研究经验，学习“黄金标准”技术实验室技能，并继续 发展成为一名有效的科学传播者、教育者和导师。因此，建议的 该项目将成为拉森女士更大的职业目标--获得一个职位--的关键一期。 一所主要研究型大学的博士研究职位和最终的教师职位。

PROJECT SUMMARY/ABSTRACT Cardiovascular disease (CVD) is the leading cause of death in the developed world. As age is a major risk factor for CVD and the average lifespan of humans is increasing, CVD is projected to reach unprecedented levels and place an enormous burden on the healthcare system. While these demographic shifts are inevitable, the development of CVD is preventable. As high blood pressure accounts for more CVD deaths than any other modifiable risk factor, interventions aimed at the management of blood pressure are crucial in preventing these sobering CVD projections from becoming reality. Heat therapy, in the form of hot bath and sauna, is an ancient practice that has recently gained attention in the treatment and prevention of CVD as regular sauna use is associated with a reduced risk of all-cause CVD deaths. Like exercise, many of the chronic benefits of heat therapy are likely mediated during the recovery period. For example, a single bout of exercise promotes a sustained reduction in blood pressure, termed post-exercise hypotension, which transiently lowers elevated blood pressure into normotensive ranges and potentiates beneficial cardiovascular adaptation with exercise training. Similarly, we and others have demonstrated a sustained reduction in blood pressure following a single bout of heat stress in both healthy and patient populations. However, the neurovascular mechanisms which underlie this post-heating hypotensive window of opportunity are unknown, representing a critical gap in knowledge. Therefore, we aim to explore post-heating hypotension, baroreflex control, and sympathetic vascular transduction in young and aged humans following whole-body heat stress. We hypothesize that post-heating hypotension is supported by downward and leftward baroreflex resetting in the absence of altered sympathetic vascular transduction in both young and aged adults. Additionally, we hypothesize that the magnitude of this blood pressure reduction and baroreflex resetting is exaggerated among aged adults. Overall, this work improves our understanding of the adaptive role of heat stress and advances heat therapy as a therapeutic option for the management of blood pressure and prevention of CVD. As the candidate, Ms. Larson completes the proposed research at the University of Oregon alongside her experienced co-mentors, Drs. Minson and Halliwill, she will gain clinical trial research experience, learn “gold-standard” technical laboratory skills, and continue to develop as an effective science communicator, educator, and mentor. As such, the proposed project will serve as an essential installment toward Ms. Larson’s larger career goal to obtain a post- doctoral research position and eventual faculty position at a major research university.