Comparative study of bepridil and nicardipine action on respiration and calcium transport in mitochondria

Effects of the calcium antagonists bepridil and nicardipine on mitochondrial functions were studied and their effects on respiratory control and calcium fluxes were compared. Results show that bepridil and nicardipine similarly increase Ca2+ intracellular movements, but that intramitochondrial Ca2+ storage is increased by bepridil whereas it is decreased by nicardipine. The in vivo significance of these findings remain to be determined. The effect of bepridil might be related to an enhancement of mitochondrial ATPase activity whereas nicardipine would act on mitochondria by a different mechanism.