Vasodilatory Effects of a New Nitroderivative of Acetylsalicylic Acid (nitropirin)

摘要

In this study we assessed the vasodilator effects of nitropirin, a new nitroderivative of aspirin, in vitro. Nitropirin contains a nitric oxide(NO) moiety, which is considered to act both by inhibiting cycloxygnase and by releasing NO in tissues. Nitropirin could relax both the endothelium-intact and endothelium-denuded rabbit aorta rings in a concentration-dependent manner. The vales of EC_50 were 7.26 x 10~-6 mol.L~-1 on the endothelium-intact aorta rings and 1.25 x 10~-5 mol.L~-1 on the endothelium-denuded aorta rings, which were considered insignificant compared with those of nitroglycerin (4.69 x 10~-6 mol.L~-1 and 5.3 x 10~-6 mol.L~ respectively, p>0.05). Aspirin showed no significant relaxant activity on aorta strips in a wide range from 1 x 10~-8 mol.L~-1 to 1 x 10~-4 mol.L~-1. The results demonstrate that nitropirin has endothelium-independent relaxant activity on the arteries. The mechanism of this property may be related to the ability of providing NO in target tissues.