We report here the protective effect of the angiotensin converting enzyme inhibitors captopril and ramiprilat against damage due to oxygen free radicals on aortic endothelium in a superfusion cascade system. Oxygen free radicals were generated by electrolysis of Krebs solution. Acetylcholine was infused through the donor aortic segment and relaxation of the detector aortic ring was used to indicate the release of endothelium-derived relaxing factor (EDRF). The percentage of relaxation before and after electrolysis was compared to calculate the relaxation index. Electrolyzed Krebs solution impa...
