Nitric Oxide Formation Contributes to β-adrenergic Dilation of Epicardial Coronary Arteries in Response to Intravenous Administration of Dobutamine in Dogs

• Published in: Journal of Huazhong University of Science and Technology. Medical sciences 2004, Vol.24 (2), p.189-191
• Main Author: 杨好意 邓又斌 毕小军 常青 白姣 潘敏 向慧娟 刘红云 李秀兰 刘娅妮 黎春蕾
• Format: Article
• Language: English
• Subjects: Adrenergic beta-Agonists - pharmacology; Animals; Coronary Vessels - physiology; Dobutamine - pharmacology; Dogs; Echocardiography; Female; Male; Nitric Oxide - physiology; omega-N-Methylarginine - pharmacology; Receptors, Adrenergic, beta - physiology; Vasodilation - physiology; β-肾上腺素受体; 一氧化氮; 动物模型; 心外膜外冠状动脉; 血管舒张功能; 静脉内治疗
• ISSN: 1672-0733; 1993-1352
• DOI: 10.1007/BF02885426

To examine the role of nitric oxide in the β-adrenergic vasodilation of epicardial coronary arteries in dogs, 12 dogs were instrumented for measurement of left anterior descending coronary artery diameter by transthoracic echocardiography before and after dobutamine (5 μg/kg/min IV)with and without intracoronary infusion of N^G-monomethyl-L-arginine (L-NMMA) (1 mg/kg). Inall 12 dogs, the diameter of left anterior descending coronary artery increased significantly from 2.35±0.25 mm to 2. 59±0. 24 mm (P＜0. 001) after dobutamine administration. In 6 of the 12 dogs, the percent change in left anterior descending coronary artery diameter induced by dobutamine decreased significantly from 12.5%±8. 6% to - 1.5%±5.4% (P＜0.05) after the administration of intracoronary L-NMMA (1 mg/kg for 5 min) to block nitric oxide synthesis from L-arginine.The study demonstrated that nitric oxide formation contributes to the β-adrenergic dilatory response of epicardial coronary arteries to dobutamine in dogs.