Egashira K, Hirooka Y, Kuga T, Mohri M, Takeshita A
Research Institute of Angiocardiology, Faculty of Medicine, Kyushu University, Fukuoka, Japan.
Circulation. 1996 Jul 15;94(2):130-4. doi: 10.1161/01.cir.94.2.130.
The pathogenesis of impaired endothelium-dependent coronary vasodilation in angina pectoris and normal coronary arteriograms (microvascular angina pectoris) is not known. We examined whether supplementation with L-arginine, a precursor of endothelium-derived nitric oxide, improves endothelium-dependent coronary vasodilation in patients with microvascular angina.
The effect of intracoronary infusion of L-arginine (50 mg/mm) on acetylcholine-induced coronary vasomotion was studied in eight patients with microvascular angina and eight control subjects. The responses of the large epicardial coronary artery diameter and coronary blood flow were measured with coronary arteriography and an intracoronary Doppler catheter, respectively. Acetylcholine increased coronary blood flow with modest vasoconstriction of the large coronary artery without altering arterial pressure and heart rate. The acetylcholine-induced increases in coronary blood flow were significantly less (P < .01) in patients than in control subjects. L-Arginine significantly augmented the coronary blood flow responses to acetylcholine in patients, but not in control subjects. L-Arginine did not alter responses of the large coronary artery in either group.
Study results suggest that L-arginine improved endothelium-dependent vasodilation of coronary microcirculation in patients with microvascular angina pectoris.
心绞痛且冠状动脉造影正常（微血管性心绞痛）患者内皮依赖性冠状动脉舒张功能受损的发病机制尚不清楚。我们研究了补充内皮源性一氧化氮的前体L-精氨酸是否能改善微血管性心绞痛患者的内皮依赖性冠状动脉舒张功能。
在8例微血管性心绞痛患者和8例对照受试者中，研究了冠状动脉内输注L-精氨酸（50mg/mm）对乙酰胆碱诱导的冠状动脉运动的影响。分别用冠状动脉造影和冠状动脉内多普勒导管测量大的心外膜冠状动脉直径和冠状动脉血流的反应。乙酰胆碱增加冠状动脉血流，同时大冠状动脉有适度的血管收缩，而不改变动脉压和心率。患者中乙酰胆碱诱导的冠状动脉血流增加显著低于（P<.01）对照受试者。L-精氨酸显著增强了患者对乙酰胆碱的冠状动脉血流反应，但对照受试者中未增强。L-精氨酸在两组中均未改变大冠状动脉的反应。
研究结果表明，L-精氨酸改善了微血管性心绞痛患者冠状动脉微循环的内皮依赖性舒张功能。
