Protective effects of benidipine on hydrogen peroxide-induced injury in rat isolated hearts

Abstract

Abstract We investigated the effects of benidipine (hydrochloride), a calcium antagonist, on hydrogen peroxide (H2O2)-induced injury in Langendorff-perfused rat hearts. The hearts were aerobically perfused at a constant flow and exposed to H2O2 (600 μmol L−1) for 4 min, resulting in the oxidative stress-induced myocardial dysfunction (e.g., decrease in the left ventricular developed pressure) and myocardial cell injury (e.g., increase in the release of lactate dehydrogenase). Pretreatment of the hearts with benidipine or nifedipine was performed for 20 min until the start of H2O2 exposure. Benidipine at 1 nmol L−1 and nifedipine at 10 nmol L−1 decreased the myocardial contractility and perfusion pressure to a similar degree in the hearts under normal conditions. Benidipine (1 nmol L−1) significantly reduced the H2O2-induced myocardial damage. Nifedipine (10 nmol L−1) also tended to exhibit similar effects. Benidipine inhibited the increase in tissue lipid peroxidation induced by H2O2. The results suggest that, in addition to the calcium antagonism, benidipine possesses other actions responsible for the cardioprotective effects, to which the antioxidant activity of benidipine may partly contribute.