[Effect of uncoupling agents and benz (a) pyrene metabolites on respiration in L cells and normal mouse embryonal fibroblasts]. / Distvie razobshchaiushchikh agentov i metabolitov benz(a)pirena na dykhanie kletok L i normal'nykh émbrional'nykh fibroblastov myshi

A method is proposed for a polarografic study of the respiration of cell suspensions obtained from monolayer cultures of L-cells and from normal embryonic fibroblasts of mice (C3HA line). 6-hydroxybenzo(a)pyrene (6-OHBP). The metabolite of the carcinogenic hydrocarbon benzo(a)pyrene, was shown to be a strong uncoupler of of oxidation and phosphorylation of cell suspensions. Its effect was influenced by the presence of calf serum in the incubation media. Possible relationships between the toxic effect of 6-OHBP on monolayer cultures of normal and tumor cells, and its effect on cell energetics are discussed.

[State of the monooxygenase enzymatic system during chronic diethylnitrosamine administration]. / Sostoianie monooksigenaznoi fermentnoi sistemy pri khronicheskom vvedenii diétilnitrozamina.

Content of components and functional activity of monooxygenase enzyme system were studied in rat liver tissue during hepatocarcinogenesis produced by diethyl nitrosamine treatment. Content of cytochromes P-450 and b5, NADPH- NADH-cytochrome c reductase and demethylase activities as well as capacity to induce the monooxygenase enzyme system after administration of its inductors were not altered in chronic treatment with carcinogenic doses of diethyl nitrosamine. The higher doses of the amine were shown to reduce the content of the cytochromes in liver tissue.