Lipoprotein(a) and oxygen free radicals in survivors of acute myocardial infarction: effects of captopril.

摘要

Long-term treatment of survivors of an acute myocardial infarction with angiotensin-converting enzyme inhibitors has a beneficial impact on their long-term outcome. We tested the hypothesis that captopril could reductively cleave the lipoprotein(a) molecule and in addition act as a scavenger of oxygen free radicals. In a double-blind trial, 20 patients were randomized to receive either captopril 50 mg daily or corresponding placebo. patients were followed for a period of 30 days. Blood samples were drawn prior to randomization and after 30 days of treatment. Plasma concentrations of lipoprotein(a) and malondialdehyde were evaluated. Captopril treatment produced a significant reduction in plasma content of lipoprotein(a) ( < 0.05) and at day 30 the plasma content of lipoprotein(a) was also significantly lower than that in the placebo group (p < 0.05). furthermore, on day 30 plasma concentrations of malondialdehyde, an indicator of oxidative damage, were significantly lower in the captopril group when compared to baseline values and corresponding placebo group values (p < 0.05). The observed effect of captopril treatment on lipoprotein(a) and malondialdehyde might be ascribed to the sulfhydryl group in the captopril molecule.