Gopal M A, Neill W A, Oxendine J M
Cardiovasc Res. 1983 May;17(5):267-73. doi: 10.1093/cvr/17.5.267.
To determine the effects of nitroprusside on regional myocardial ischaemia, experiments were done in 11 conscious dogs with balloon-cuff occluders implanted around the left anterior descending coronary artery (LAD). Regional myocardial blood flow by the microsphere method was determined during 5 min periods of temporary LAD occlusion with and without nitroprusside infusion. Nitroprusside decreased aortic mean and left ventricular diastolic pressures. Blood flow increased to ischaemic myocardium supplied by the occluded LAD and to non-ischaemic myocardium supplied by the patent left circumflex coronary artery. Experiments were repeated on a separate day in the presence of left ventricular distension in the same dogs. Nitroprusside again decreased aortic mean and left ventricular diastolic pressures and increased the blood flow to both ischaemic and non-ischaemic myocardial regions. These results suggest that nitroprusside can improve perfusion to acutely ischaemic myocardial tissue despite a fall in aortic pressure, presumably by decreasing resistance to flow in coronary collateral vessels or by decreasing the myocardial tissue pressure.
为了确定硝普钠对局部心肌缺血的影响，对11只清醒犬进行了实验，这些犬的左冠状动脉前降支（LAD）周围植入了气囊袖带闭塞器。在用微球法测定局部心肌血流量时，在临时阻断LAD 5分钟的期间内，分别进行有无硝普钠输注的操作。硝普钠降低了主动脉平均压和左心室舒张压。血流量增加到由闭塞的LAD供血的缺血心肌以及由通畅的左旋冠状动脉供血的非缺血心肌。在同一天，对同一些犬在存在左心室扩张的情况下重复进行实验。硝普钠再次降低了主动脉平均压和左心室舒张压，并增加了缺血和非缺血心肌区域的血流量。这些结果表明，尽管主动脉压下降，但硝普钠仍可改善急性缺血心肌组织的灌注，这可能是通过降低冠状动脉侧支血管的血流阻力或降低心肌组织压力来实现的。
