[Respiratory phosphorylation in the liver mitochondria of rats with transplantable sarcomas].
Cuvinte cheie
Abstract
The method of polarography was used to study respiration and phosphorylation capacity of the hepatic mitochondria in rats with transplantable sarcoma 45 and Walker carcinosarcoma in different terms after transplantation, and in spontaneous regression of the tumors involved, as well. In the hepatic mitochondria of tumor-bearing animals a marked dissociation of respiration and phosphorylation is observed, being mostly manifested in oxidation of glutamate and endogenic NAD-dependent substrates. Non-phosphorylating oxidation suffers to a less extent. Experiments with the use of rhothenon indicated that an impaired rate of the coupling of oxidation and phosphorylation was also related with a destroyed succinate site in the respiratory chain. In the presence of serum albumin an up to normal values restoration of the rate of respiration and phosphorylation coupling is observed in the hepatic mitochondria of tumor-bearing animals. The degree of interference in the respiratory phosphorylation process is mostly significant at late stages of tumors development and sharply declines in their spontaneous regression.