IN VIVO ENDOTHELIAL INJURY AND DEPENDENT VASOMOTION

内皮依赖性血管舒张功能受损 （EDVR）在体内冠状动脉中可能与 部分由冠状动脉风险引起的内皮损伤量 因素和动脉粥样硬化的猪和病人， 降低风险因素。 动脉血管收缩可以 减少血流量，增加动脉壁剪切力， 增加血小板在受损动脉中的沉积， 动脉粥样硬化斑块的突然破裂。 内皮 可以代谢和减少壁内扩散 管腔内血管收缩物质（血小板产物和 儿茶酚胺），防止血小板活化和随后的 释放血小板血管收缩物质，并促进 通过前列环素的产生和释放进行血管舒张， 内皮源性舒张因子（EDRF）。 在猪中，我们将检验节段性冠状动脉 EDVR的动脉损害（通过定量测量） 血管造影），以乙酰胆碱（EDRF- 释放剂）与内皮损伤的程度相关 （通过111 In标记的自体血小板的程度来定量 沉积（血小板数量/立方厘米）和表面的百分比 伊文思蓝染色区域）（a）由轻度球囊扩张诱导， （B，c）内皮样细胞再生长4天和8天后 球囊损伤后，（d）通过4个月的2%胆固醇喂养诱导 (e)4个月后愈合或内皮再生后 停止胆固醇喂养，（f）8个月4%诱导 胆固醇喂养，在近端，覆盖，和远端的位置 大于50%的动脉粥样硬化病变，和（g）4个月后 停止4%胆固醇喂养。 EDVR的节段性冠状动脉损害 （通过定量冠状动脉造影测量）至分级 乙酰胆碱的输注可以作为研究 内皮损伤的严重程度（以及 愈合或再生长）在最小病变的冠状动脉中 在（a）降低升高的甘油三酯和 胆固醇，（B）降低升高的胆固醇，和（c） 戒烟。 节段性冠状动脉损伤 EDVR也可以是用于测量时间和程度的探针， 球囊部位近端和远端的内皮愈合 血管成形术（存在内皮损伤但无平滑 肌肉细胞坏死），在产瘤动脉中， 心肌梗死或不稳定型心绞痛，以及用于确定 冠状动脉危险因素的最佳降低水平 内皮的愈合。

The impairment of endothelial-dependent vascular relaxation (EDVR) in vivo in coronary arteries is probably related to the amount of endothelial injury induced in part by coronary risk factors and atherosclerosis in pigs and patients and may be reduced by risk factor reduction. Vasoconstriction in arteries can reduce blood flow, increase arterial wall-shear forces which increases platelet deposition in injured arteries, and may precipitate rupture of atherosclerotic plaques. The endothelium can metabolize and reduce the intramural diffusion of intraluminal vasoconstrictive substances (platelet products and catecholamines), prevent platelet activation and subsequent release of platelet vasoconstrictive substances, and promote vasodilation via the production and release of prostacyclin and endothelial-derived relaxing factor (EDRF). In the pig, we will test the hypothesis that the segmental coronary arterial impairment of EDVR (measured by quantitative angiography) to graded infusions of acetycholine (an EDRF- releasing agent) correlates with the extent of endothelial injury (quantitated by the degree of 111 In-labeled autologous platelet deposition (no. of platelets/cubic cm.) and the percent of surface area stained by Evans blue) (a) induced by mild balloon dilatation, (b, c) following regrowth of endothelial-like cells 4 and 8 days after balloon injury, (d) induced by 4 mo of 2% cholesterol feeding (e) following healing or regrowth of endothelium after 4 mo withdrawal of cholesterol feeding, (f) induced by 8 mo of 4% cholesterol feeding, in locations proximal, overlying, and distal to a greater than 50% atherosclerotic lesion, and (g) 4 mo after withdrawal from 4% cholesterol feeding. In patients segmental coronary arterial impairment of EDVR (measured by quantitative coronary angiography) to graded infusions of acetylcholine can be a probe to investigate the severity of endothelial injury (and the extent and timing of healing or regrowth) in minimally diseased coronary arteries before and after (a) reduction of elevated triglycerides and cholesterol, (b) reduction of elevated cholesterol, and (c) cessation of smoking. Segmental coronary arterial impairment of EDVR can also be a probe for measuring the timing and degree of endothelial healing just proximal and distal to the site of balloon angioplasty (where there is endothelial damage but no smooth muscle cell necrosis), in the symptom-producing artery after myocardial infarction or unstable angina, and for determining the level of coronary risk factor reduction necessary for optimal healing of the endothelium.