CORONARY VASODILATION BY NITRATES IS NOT MEDIATED BY THE PROSTAGLANDIN SYSTEM - A QUANTITATIVE CINEANGIOGRAPHIC STUDY

[摘要] The possible role of prostaglandins in mediating large coronary artery vasodilation by nitrates was investigated by quantitative magnification coronary angiography. The effects of aspirin (1 g systemically and 100 mg intracoronary) in preventing large coronary artery vasodilation induced by intracoronary isosorbide dinitrate was investigated in 16 patients. Of these, 5 received 0.3 mg (Group IA) and 11 received 3 mg (Group 1B) intracoronary isosorbide dinitrate, before and 15 minutes after aspirin. Relative to control, 0.3 mg isosorbide dinitrate induced a 19 .+-. 9% (mean .+-. SD) (p < 0.01) and 19.5 .+-. 11% (p < 0.01) increase in coronary diameter before and after aspirin, respectively (p = NS). Changes after 3 mg isosorbide were 23 .+-. 12% (p < 0.01) and 26.5 .+-. 14% (p < 0.01), respectively, before and after aspirin (p = NS). In 10 additional patients (Group 2), the effct of the same dose of aspirin on rest coronary artery tone was assessed: changes relative to control were 0.9 .+-. 5.5% (p = NS) minutes after aspirin. The intracoronary administration of 3 mg isosorbide dinitrate produced a 24.7 .+-. 11% increase in coronary diameter (p = NS versus pre- postaspirin isosorbide in Group 1B). Urinary 6-ketoporostaglandin-F1.alpha. values in urine samples collected in the 8 hours before and the 8 hours after the study in five patients in Group 1B and five patients of Group 2, revealed a 26 .+-. 14% (mean .+-. SD) reduction in excretion of prostacyclin (p < 0.01). These data rule out a role of prostaglandins both in mediating dilation of large coronary arteries by nitrates and in affecting their vascular tone at rest.

[发布日期] 1986-12-01