CARDIAC DENERVATION AND PSYCHOPHYSIOLOGICAL REACTIVITY

这是重新提交的关于继续支持利用 人心脏移植失神经心脏模型的建立 受试者测试心理生理反应性的详细程度 冠心病(CAD)假说。这一假设认为 需要完整的心脏自主控制系统来缓冲增加 在应对心理挑战时的血压变异性 接受测试。最近的证据表明，血压变异性是 独立于平均动脉压的心脏病危险因素。 据推测，心脏自主神经控制能力减弱 刺激引起的血压变异性反应升高 转弯会增加患冠心病的风险。 心脏搏动周期、血压和动脉化血浆 将在28名心脏移植受者中检测去甲肾上腺素 年龄和性别匹配的正常对照和肾脏样本大小相等 移植受试者在安静的静息基线和对 心算和Stroop颜色词任务。心脏自主神经 控制，操作为心脏周期变异性和血压 可变性将通过既定的时间序列方法计算。这个 缺乏心脏自主神经控制，如实质上缺乏心脏自主神经控制 心脏周期变异性在心脏移植中是公认的 收件人。据预测，由于这大大减少了心脏 自主控制，心理挑战会导致显著 心脏的低频血压变异性增加更多 移植受者与其他两组相比，这一点 在移植后的第一年，差异将保持稳定。 心脏移植受者是最具戏剧性的 心脏自主神经控制减弱，因此，最清楚的测试是 这个假说。然而，这一假说不仅与心脏有关 移植患者，其中CAD的发展是很大的 与整体人口相比加速增长，但也在 心脏神经完好但心脏自主神经减少的个体 控制力。这些患者包括抑郁症、焦虑症和 糖尿病神经病变，以及高度敌意的健康个体， 所有这些人都增加了患冠心病的风险。因此，虽然在这个 应用，仅心脏移植受者和适当的控制 对群体进行了研究，支持这一假说与许多人相关 人群，健康的和其他的，自主控制能力降低。

This is a resubmission of a proposal for continuing support to utilize the model provided by the denervated heart of human cardiac transplant recipients to test an elaboration of the psychophysiological reactivity hypothesis of coronary artery disease (CAD). The hypothesis that the intact cardiac autonomic control system is required to buffer increases in blood pressure variability in response to psychological challenge will be tested. Recent evidence suggests that blood pressure variability is a risk factor to cardiac disease independent of mean arterial pressure. It is hypothesized that diminished cardiac autonomic control permits elevated challenge-induced blood pressure variability responses which in turn are associated with increased risk of CAD. Beat-to-beat heart period and blood pressure and arterialized plasma norepinephrine will be measured in 28 cardiac transplant recipients and equal-sized samples of age- and gender-matched normal control and renal transplant subjects during a quiet resting baseline and in response to mental arithmetic and Stroop color-word tasks. Cardiac autonomic control, operationalized as heart period variability, and blood pressure variability will be computed by established time series methods. The absence of cardiac autonomic control, as indicated by virtual absence of heart period variability, is well-established in cardiac transplant recipients. It is predicted that due to this greatly reduced cardiac autonomic control, psychological challenge will lead to significantly greater increases in low frequency blood pressure variability in cardiac transplant recipients compared to the other two groups and that this difference will be stable over the first year following transplantation. Cardiac transplant recipients represent the most dramatic case of diminished cardiac autonomic control and, therefore, the clearest test of this hypothesis. However, the hypothesis is relevant not only to cardiac transplant patients, in whom the development of CAD is greatly accelerated compared to the population as a whole, but also in individuals with intact cardiac nerves but reduced cardiac autonomic control. These include patients with depression, anxiety disorders, and diabetic neuropathy, as well as healthy individuals high in hostility, all of whom have increased risk of CAD. Thus, although in this application, only cardiac transplant recipients and appropriate control groups are studied, support for this hypothesis is relevant to many populations, healthy and otherwise, with reduced autonomic control.