Coronary arterial vasodilator effect of ibuprofen

The effect of ibuprofen, a nonsteroidal anti-inflammatory agent, on coronary vascular resistance in isolated perfused rabbit heart was studied. Ibuprofen had coronary arterial vasodilatory activity. An arterial concentration of 50 microgram/ml produced a half-maximal coronary vasodilator response. An ibuprofen concentration of 140 microgram/ml produced a coronary vasodilation, equal to that caused by hypoxia. A level of 280 microgram/ml depressed contractile function. The change in coronary vascular resistance did not appear to be physiologic autoregulation of coronary tone because determinants of myocardial oxygen demand were not significantly affected and myocardial oxidative metabolism was not significantly impaired, as reflected by myocardial lactate extraction, which was not significantly affected during the ibuprofen-induced coronary dilation. These results suggest a direct effect of ibuprofen on coronary vascular resistance.