NEURAL CONTROL OF THE CORONARY CIRCULATION IN HUMANS

交感神经和体液刺激对冠状动脉的影响 血管阻力直接通过对冠状动脉的影响 并间接通过对心肌的影响。虽然 动物研究表明，心脏的间接扩张器效应 交感神经刺激通常盖过直接收缩肌 效应，最近的研究表明，直接效应可以发挥 在控制冠状动脉血管阻力中起主导作用。 冠状动脉血管阻力的神经控制研究进展 人类是有限的，而且很难获得，主要是因为 方法论上的原因。我们最近开发了和 验证了一种小型腔内多普勒导管，可以 测量清醒人体冠脉血流时相速度。 我们将利用这个导管来研究冠脉血流速度。 对反射和直接交感刺激的反应要求三个 问题：1)神经性收缩反应加重了吗？ 在出现高胆固醇血症时没有明显的 冠状动脉病变？2)这种反应在存在的情况下会加重吗 冠状动脉粥样硬化？3)β受体阻滞剂揭开面纱 慢性阻塞性肺疾病患者肾上腺素能冠状动脉血管收缩加重 冠状动脉损伤？利用冠脉血流速度反应 冠脉内罂粟碱作为选择性血管扩张剂的研究 储备和定量冠状动脉造影术评估病变 几何学，我们将学习血管扩张剂储备，病变几何学，以及 正常人和正常人冠脉血流速度的神经控制 冠状动脉粥样硬化患者。这种方法论应该 使我们能够获得对神经调节的基本新见解 人类冠脉循环的研究。

Sympathetic neural and humoral stimuli influence coronary vascular resistance directly through effects on coronary vessels and indirectly through effects on the myocardium. Although animal studies suggest that the indirect dilator effects of sympathetic stimulation usually overshadow direct constrictor effects, recent work has shown that direct effects can play a dominant role in control of coronary vascular resistance. Information on neural control of coronary vascular resistance in humans is limited and has been difficult to obtain primarily for methodological reasons. We have recently developed and validated a small intralumenal Doppler catheter which can measure phasic coronary blood flow velocity in conscious humans. We will utilize this catheter to study coronary blood flow velocity in response to reflex and direct sympathetic stimuli asking three questions: 1) Is the neurogenic constrictor response accentuated in the presence of hypercholesterolemia without significant coronary lesions? 2) Is this response accentuated in the presence of coronary atherosclerosis? 3) Does beta blockade unmask accentuated adrenergic coronary vasoconstriction in patients with coronary lesions? Using the coronary blood flow velocity response to intracoronary papaverine as a measure of selective vasodilator reserve and quantitative coronary angiography to assess lesion geometry, we will study vasodilator reserve, lesion geometry, and neural control of coronary blood flow velocity in normals and patients with coronary atherosclerosis. This methodology should allow us to obtain fundamental new insights into neural regulation of the coronary circulation in humans.