抄録
We studied the antioxidant activities of calcium antagonists against autoxidation in rat brain homogenates.The homogenates were incubated for 30 min at 37°C with or without a calcium antagonist and subsequently assayed for lipid peroxide content. Percent inhibition of the lipid peroxidation was used as an index of the antioxidant effect. Dihydropyridine calcium antagonists exhibited concentration-dependent (3-300 μmol/l) inhibitory effects against lipid peroxidation. The relative order of antioxidant potency and associated IC50 values (μmol/l) of the calcium antagonists for inhibition of the lipid peroxidation were as follows : nifedipine (51.5)>barnidipine(58.6)>benidipine (71.2)>nicardipine (129.3)>amlodipine (135.5)>nilvadipine (167.3)>nitrendipine (252.1)>>diltiazem (>300)=verapamil (>300). These results suggest that some dihydropyridine calcium antagonists show antioxidant properties. The antioxidant effects of the calcium antagonists may contribute to their pharmacological actions.
