SEX DIFFERENCES IN REPOLARIZATION AND EARLY REPOLARIZATION (AIM 3)

这个子项目是利用由NIH/NCRR资助的中心拨款提供的资源的许多研究子项目之一。子项目和调查员(PI)可能从另一个NIH来源获得了主要资金，因此可能会出现在其他CRISE条目中。列出的机构是针对中心的，而不一定是针对调查员的机构。在这个项目中，我们假设性激素水平是心肌复极(ST段高度)的主要决定因素。支持这项研究的理论基础是，在某些心律失常(不规则心跳)的易感性方面存在重要的性别差异，这表明男性和女性之间存在基本的电生理差异。为了验证我们的假设，我们将研究在没有接受激素替代治疗的心脏病患者和没有接受正常替代治疗的患者中，ST段高度与性激素水平之间的关系。具体地说，受试者将接受超声心动图(一种利用声波勾勒心脏大小并确定心脏运行状况的测试)，被要求在固定自行车上进行运动测试(记录受试者在踏板时的心脏电活动)，如果女性有规律的月经周期，则接受尿液排卵预测测试，并给20毫升的血液测定几种性激素水平。我们将寻求根据正常月经周期不同阶段和长期性激素治疗后发生的激素水平变化来确定ST变量的变化幅度。

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. In this project, we hypothesize that the level of sex hormones is a major determinant of myocardial repolarization (ST height). The rationale supporting this study is that there are important sex differences in susceptibility to certain arrhtyhmias (irregular heartbeats), suggesting the existence of fundamental electrophysiologic distinctions between males and females. To test our hypothesis, we will examine the relationship between ST height and sex hormone levels in a mixed population of subjects (young and old men and women) without heart disease undergoing hormonal replacement therapy and in subjects not undergoing hormal replacement therapy. Specifically, subjects will be given an echocardiogram (a test using a sound wave that outlines the size of the heart and determines how well the heart is functioning), asked to do an exercise test on a stationary bicycle (which records the heart's electrical activity while the subject is pedaling), undergo, if females with regular menstrual cycles, a urinary ovulation predictor test and give 20 ccs of blood to determine several sex hormone levels. We will seek to determine the magnitude of changes in ST variables according to hormone levels changes occuring during the different phases of a normal menstrual cycle and following a long-term sex hormones therapy.