We examined a possible mechanism of action of an ATP-sensitive potassium (K(ATP)) channel opener, YM934, for the improvement of energy metabolism in hearts subjected to 35-min ischemia and 60-min reperfusion. The treatment with 30 nM YM934 for the final 15 min of preischemia enhanced postischemic recovery of left ventricular developed pressure, attenuated the postischemic rise in left ventricul...

We investigated the role of the mitochondrial ATP-sensitive K(+) (K(ATP)) channel, the mitochondrial big-conductance Ca(2+)-activated K(+) (BK(Ca)) channel, and the mitochondrial permeability transition pore (MPTP) in the ouabain-induced increase of mitochondrial Ca(2+) in native rat ventricular myocytes by loading cells with rhod 2-AM. To overload mitochondrial Ca(2+), we pretreated cells with...

The energy demand of cardiomyocytes changes continuously in response to variations cardiac workload. Cardiac excitation-contraction coupling is fueled primarily by adenosine triphosphate (ATP) production oxidative phosphorylation mitochondria. rate mitochondrial metabolism matched the ATP consumption cytosol parallel activation calcium (Ca 2+ ) and diphosphate (ADP). During workload transitions...

BACKGROUND AND PURPOSE Mitochondrial ATP-sensitive potassium (mitoK(ATP)) channels are present in the brain, and several reports have shown that mitoK(ATP) channel openers protect the brain against ischemic injury. However, the precise mechanisms of this protection are not well established. We hypothesized that mitoK(ATP) channel openers prevent apoptosis by preserving mitochondrial membrane po...

Objective(s): This work aimed to assess the effect of 10 new chromon-3-aldehyde derivatives on changes of mitochondrial function under the conditions of brain ischemia in rats. Materials and Methods: The work was executed on BALB/c male-mice (acute toxicity was evaluated) and male Wistar rats, which were used to model cerebral ischemia b...

ATP is involved in conferring transport competence to numerous mitochondrial precursor proteins in the cytosol. Unfolded precursor proteins were found not to require ATP for import into mitochondria, suggesting a role of ATP in the unfolding of precursors. Here we report the unexpected finding that a hybrid protein containing the tightly folded passenger protein dihydrofolate reductase becomes ...

Human cervical cancer HeLa cells have functional mitochondria. Recent studies have suggested that mitochondrial metabolism plays an essential role in tumor cell proliferation. Nevertheless, how cells coordinate mitochondrial dynamics and cell cycle progression remains to be clarified. To investigate the relationship between mitochondrial function and cell cycle regulation, the mitochondrial gen...

Pioglitazone (PG) is one of thiazolidinediones used for the treatment of type II diabetes mellitus. Some reports of its hepatotoxicity exist, but the mechanism of its hepatotoxicity is not well known. In the present study, the protective effect of some ATP suppliers are investigated against mitochondrial toxicity of PG in isolated rat mitochondria. Mitochondrial viability was investigated by MT...

Earlier work has shown that mitochondrial proteins synthesized in the cytosol are initially made as larger precursors which are then transferred into the organelles and processed to their mature size in the absence of protein synthesis. It is now demonstrated that depletion of the mitochondrial matrix ATP in intact yeast spheroplasts by various combinations of inhibitors and mutations prevents ...