[Effect of papaverine on the energy processes of myocardial mitochondria]

In experiments with dog's myocardial mitochondria the influence of different doses of papaverine on the succinate, glutamate and alpha-ketoglutarate oxidation was studied. The drug effect depended on its dose, it not being related to the substrate transport across the mitochondrial inner membrane and not resulting from the block of the respiratory chain between NAD.H and cytochrome b. The papaverine action is possibly due to the inhibition of specific dehydrogenases. The glutamate oxidase system proves most sensitive to inhibition produced by papaverine, while the alpha-ketoglutarate oxidase system is less susceptible to the effect of this drug. The succinate oxidase system is found to be least sensitive to the action of papaverine.