BIOBEHAVIORAL MECHANISMS OF BLOOD PRESSURE REGULATION

高血压在黑人男性中比白人男性更普遍，而且 在男性中比在女性中流行。此外，即使控制血液 压力，向心性左心室肥厚，早期结构性 适应高血压在黑人男性中比白人男性更普遍，而且 在男性中比女性中更常见。向心性左心室肥厚 是除年龄外，心血管疾病的最强预测因子 与高血压相关的发病率。拟议的研究将 探讨生物行为因素在青光眼发病机制中的作用 向心性左心室肥厚。 200例正常血压和临界性高血压患者的双胎样本 年龄在25岁至39岁之间的男性和女性将接受测试。同心左 心肌肥厚和向心性重构将通过 超声心动图测量左心室重量和相对壁厚 厚度。实验室程序将用于：(I)评估血流动力学 以及在暴露于不同的电池时的神经体液反应 生理和心理应激源，以及；(2)评估阿尔法和贝塔 肾上腺素能受体反应性、压力感受器反射增益和最小 前臂血管阻力。因为在一个典型工作日的血压 是左心室肥厚的既定预测指标，它也会 被评估。 一种新的生物行为模型将被测试，该模型涉及血液动力学 行为诱发升压反应在心力衰竭发病机制中的作用 向心性左心室肥厚。这个模型的一个预测是 一种表现出血管阻力增加的倾向 压力(黑人男性的特征)将有利于 向心性肥厚。因此，全身血管阻力反应， 在实验室进行评估，被假设为独立预测 左心室重量和相对室壁厚度，即使在控制后 对于已确定的风险因素，包括工作日血压。 交感神经系统功能将被检查以检验假设 血流动力学中种族和性别差异的机制 血压调节的模式。这些研究的结果应该是 强调种族和性别在药物处方中的重要性 和/或高血压心脏病的行为治疗。

Hypertension is more prevalent in black than white men, and is more prevalent in men than women. Furthermore, even controlling for blood pressure, concentric left ventricular hypertrophy, an early structural adaptation of hypertension, is more prevalent in black than white men, and more prevalent in men than women. Concentric left ventricular hypertrophy is the strongest predictor, other than age, of the cardiovascular morbidity associated with high blood pressure. The proposed research will investigate the role of biobehavioral factors in the pathogenesis of concentric left ventricular hypertrophy. A biracial sample of two hundred normotensive and borderline hypertensive men and women aged 25-39 years, will be tested. Concentric left ventricular hypertrophy and concentric remodelling will be assessed by echocardiographic measures of left ventricular mass and relative wall thickness. Laboratory procedures will be used to: (i) assess hemodynamic and neurohumoral responses during exposure to a diverse battery of physical and psychological stressors, and; (ii) evaluate alpha and beta adrenergic receptor responsiveness, baroreceptor reflex gain and minimal forearm vascular resistance. Since blood pressure during a typical workday is an established predictor of left ventricular hypertrophy, it will also be assessed. A new biobehavioral model will be tested that implicates the hemodynamic pattern of behaviorally-evoked pressor responses in the pathogenesis of concentric left ventricular hypertrophy. One prediction of this model is that a predisposition to exhibit increased vascular resistance during stress (characteristic of black men) will favor the development of concentric hypertrophy. Thus, systemic vascular resistance responses, evaluated in the laboratory, are hypothesized to independently predict left ventricular mass and relative wall thickness, even after controlling for established risk factors, including workday blood pressure. Sympathetic nervous system function will be examined to test hypothesized mechanisms responsible for race and gender differences in the hemodynamic patterns of blood pressure regulation. The results of these studies should emphasize the impOrtance of race and gender in prescribing pharmacological and/or behavioral treatment for hypertensive heart disease.