[Action of strong and weak nitrogenous bases on respiratory chain enzymes of mitochondria]

The action of nitrogenous basis--electroneutral hydrazides (pK less than 7,50 and positive charged arylhydrazones (pK greater than 8)--on the respiratory chain enzymes and the influence of the electric charge and the size of alkoxylic group on biological activity compounds have been investigated. It has been shown that the size of alkoxylic group defines the selective action of nitrogenous basis on the enzymes of mitochondrial respiratory chain. The nitrogenous basis with a long alkoxylic group is shown to be inhibitors of NADH-dehydrogenase, their action is similar to rotenone. At the same time compounds with a short group are more effective in the inhibition of the enzymes of the initial segment in the respiratory chain mitochondria. The affinity of the organic cations of arylhydrazones to NADH-dehydrogenase is 100-1000 times higher than the affinity of electric neutral compounds.