ENDOTHELIAL DYSFUNCTION IN PATIENTS WITH MICROVASCULAR ANGINA

血管的衬里，称为内皮，能够 分泌允许血管放松的物质，以响应 各种刺激。释放的一种因子被称为内皮细胞衍生 松弛因子(EDRF)。乙酰胆碱能促进EDRF的释放 来自血管。内皮功能缺失或功能障碍可导致 乙酰胆碱引起的血管扩张或收缩减弱。一点儿 有关EDRF在小血管中的作用的信息可用 心脏患者有胸痛和正常的大冠状动脉。我们 研究有胸部、心外膜冠状动脉正常的患者 而心房起搏则减少了血管的扩张。这些患者还 对乙酰胆碱输注的内皮依赖性血管扩张作用减弱 注射在冠状动脉中。然而，他们有正常的反应， 硝普钠，一种内皮非依赖性血管扩张剂。因此，患有 对心房起搏的血流反应受损也会降低对 内皮依赖性血管扩张，但不依赖于非血管扩张剂 依赖于完整的内皮细胞。这些结果表明，患有 微血管心绞痛(胸痛和冠状动脉正常) 血管扩张储备受损，也可能有血管内皮细胞异常 他们冠状动脉的小血管。

The lining of blood vessels, called the endothelium, is capable of secreting substances which allow blood vessels to relax in response to a variety of stimuli. One factor released is known as endothelium-derived relaxant factor (EDRF). Acetylcholine is able to promote release of EDRF from blood vessels. Absence or malfunction of the endothelium can lead to diminished dilation or vasoconstriction with acetylcholine. Little information is available on the role of EDRF in small blood vessels of the heart in patients with chest pain and normal large coronary arteries. We studied patients with normal epicardial coronary arteries who had chest pain, and on atrial pacing had reduced vasodilation. These patients also had a reduced endothelial-dependent vasodilation to acetylcholine infusions given in the coronary arteries. However, they had normal reaction to nitroprusside, an endothelial-independent vasodilator. Thus, patients with impaired flow response to atrial pacing also have a reduced response to endothelial-dependent vasodilation, but not to a vasodilator which is not dependent on intact endothelium. These results suggest that patients with microvascular angina (chest pain and normal coronary arteries) who have impaired vasodilator reserve, may also have an endothelial abnormality in the small vessels of their coronary arteries.