Ropinirole: another neuroprotectant blocking the permeability transition pore in the inner mitochondrial membrane

More and more neuroprotectants are found that seem to act by interrupting the signaling chain leading to apoptosis. A central step within this cascade is opening of the permeability transition pore (PTP). In contrast, blockade of the PTP is able to suppress apoptotic cell death as was shown with melatonin (Andrabi et al., 2004, FASEB J, 18:869). After demonstrating such an effect for the dopamine agonist pramipexole, we show here that another nonergot dopamine-D2-agonist, ropinirole, causes PTP blockade as well. We prepared mitoplasts i.e. vesicles of inner mitochondrial membrane by a hypotonic treatment of the…