Estradiol prevents ischemia-induced release of cytochrome c from heart mitochondria

Abstract

It has been shown that estrogens play a cardioprotective role in global myocardial ischemia-reperfusion in female rats, however, the mechanism is unclear. We have previously reported that 17β-estradiol can protect heart mitochondria from the loss of cytochrome c induced by high calcium [4]. In this study we aimed to elucidate whether estradiol can prevent release of cytochrome c from mitochondria and subsequent inhibition of respiration after 30 min stop-flow ischemia in Langendorffperfused rat female hearts. We found that pre-perfusion of hearts with 100 nM of 17β-estradiol (high physiological concentration) partially prevented the loss of cytochrome c from mitochondria and subsequent inhibition of mitochondrial respiration. These data suggest that the cardioprotective effect of estrogens against ischemic damage might be partly related to their direct effect on mitochondria. Keywords: heart, mitochondria, estrogen, cytochrome c, respiration