[The cytotoxicity of Chamaenerium angustifolium (L.) Scop. and Hippophae rhamnoides L. tannins and their effect on mitochondrial respiration].

The cytotoxic activity of complexes of hydrolysable tannins of Chamaenerium angustifolium L. Scop. and Hippophae rhamnoides L. was compared with that of the antineoplastic drugs vinoblastin (VLB), methotrexate (MT), and 5-fluorouracil (5-FU). The tannins yield to VLB and MT in activity but resemble 5-Fu in their active concentration. They inhibited succinate oxidation by the rat liver mitochondria and their cytotoxicity was displayed in much lower concentrations than their inhibitory effect on mitochondrial respiration. It is concluded that tannins inhibit the respiratory chain at the third point of conjugation in the transfer of electrons from cytochrome c to oxygen.