Effect of oxodipine on calcium transport in isolated hepatocytes and rat liver mitochondria at different ages.
Electron microscopy and biochemical studies were carried out in hepatocytes and mitochondria isolated from livers of young (3-6 month) and old (20-24 month) rats to know under which conditions oxodipine, a calcium antagonist, affects calcium metabolism, the mitochondrial morphology and the differences due to the animals age. Under steady-state conditions, calcium transport through the membrane of isolated hepatocytes was not affected by the presence of the drug in either group of animals studied. By contrast, a clear age-dependent inhibitory effect on the uptake and accumulation of calcium was observed in mitochondria. In the young animals, evidence was observed for a complex mechanism related to cellular respiration and to a possible specific action of the drug. In older animals, this second mechanism appears to be very weak or inexistent. Quantitative morphological studies also point to a deterioration in the mitochondria due to the effect of the drug at the concentrations at which cellular respiration was affected.
Roncero
I
I
Departamento de Bioquímica, Facultad de Medicina, Universidad Complutense, 28040 Madrid, Spain.
Buron
I
I
de la Cruz
M J
MJ