[Toxicologic evaluation of individual chemical compounds and complex mixtures using a motile cell test object].

The possibility of quantitative prognosis of chemical compounds and complex mixtures toxicity by means of a biotechnical system with suspension of bull spermatozoa sensor was investigated. The concentration of some chemical compounds, inhibiting by half spermatozoa motility has been experimentally determined. A correlation between the values determined and acute toxicity of the compounds tested has been established.

[Study of promutagen biotransformation in the Ames test. III. The role of conjugation with glucuronic acid and sulfate in the modification of mutagenic effect of nitrosomorpholine, diethylnitrosamine and cyclophosphamide].

The role of reactions of conjugation with uridine diphosphoglucuronic acid (UDPGA) and with 3-phosphoadenosine-5-phosphosulfate (PAPS) in modification of the mutagenic effect of diethyl nitrosamine (DENA), nitrosomorpholine (NM) and cyclophosphane (CP) was studied by the Ames test. It was shown that adding UDPGA to the activating mixture significantly decreased the level of the mutagenic effect of DENA, NM and CP on bacteria Salmonella typhimurium TA 1950, when S9 and microsomal fractions of rat liver homogenate were used. Adding PAPS to the activating mixture when S9 and cytosole fractions were used, did not affect mutagenic action of DENA on S.

[Study of the process of promutagen biotransformation by the Ames test. I. The role of conjugation with glutathione in the modification of the mutagenic activity of nitrosomorpholine, diethylnitrosamine and cyclophosphamide].

It is demonstrated that the level of the action of nitrosomorpholine (NM), diethyl nitrosoamine (DENA) and cyclophosphane (CP) promutagens on bacteria is lowered as a result of the Ames test modification by means of addition of reduced glutathione (G-SH) to the activating mixture. The data are presented on the dependence of this phenomenon on concentration of promutagens and G-SH, the period of bacteria preincubation with the compound under study and the activating mixture as well as on concentration of microsomal protein. No changes in the mutagenic effect of NM, DENA and CP were observed when G-SH was substituted for cysteine in equimolar concentration.

[Classification of xenobiotics according to their effect on mitochondrial enzymatic systems].

The author reviews his own and reported data on the action of toxic substances of varying chemical classes on the main stages of the process of oxidative phosphorylation. It has been shown that toxic substances can destroy oxidative phosphorylation by the following ways: by reducing the resistance of mitochondrial membranes (disconnectors of the protonophoric and ionophoric types); by inhibiting dehydrogenase activity; by disturbing electron transfer via the respiratory chain; by disordering transmembrane transport of cations or anions; by inhibiting ATPase activity. The characteristic classes of toxic substances and the most specific inhibitors are indicated for each of the points enumerated.

[Peculiarities of alkyl tin effects on respiration and oxidative phosphorylation of rat liver mitochondria].

Electron transfer and oxidative phosphorylation were studied as affected by tinalkyls. It is shown that all of them inhibit effectively respiration of the rat liver mitochondria. The action of bis(tributyl tin)oxide and dibutyl diisooctyl thioglycolate tin on the mitochondria in a state of dissociation is localized in the terminal step of the respiration chain.