A study on constrictor response of dog coronary arteries to acetylsalicylic acid

The present study was designed to investigate the effects of acetylsalicylic acid at a high dose on dog coronary arteries. In the isolated and perfused dog hearts, an intracoronary injection of acetylsalicylic acid (10 mg) decreased coronary blood flow concomitant with diminution of myocardial contractile force, but did not change heart rate. In the isolated dog coronary arterial strips, acetylsalicylic acid (10-4 M) produced the contractions of them, which were significantly inhibited by calcium-free solution, diltiazem, nifedipine, phospholipase A2, arachidonate and prostaglandin E1. The results indicate that acetylsalicylic acid at a high dose produces coronary arterial contracture probably through inhibition of intravascular synthesis of vasodilating prostaglandins.