[Bioassay using spermatozoa suspensions].
Explore the source record for details and available documents.
Biomedical subjects
Publications and source records attributed to Iu S Rotenberg.
Explore the source record for details and available documents.
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. The possible use of the biotechnical system for the screening of medical polymer materials has been demonstrated.
Explore the source record for details and available documents.
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. typhimurium TA 1950 and TA 1535, enhancing the mutagenic effect of CP on TA 1535, with no such influence on TA 1950. Introduction of PAPS into the activating mixture elevated the mutagenic effect of NM on both bacterial strains using S9 fraction but not cytosole fraction.
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. This fact points to enzymic mechanism involved in elimination of the damaging effect of mutagenic metabolites of the compounds studied.
Explore the source record for details and available documents.
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. It is pointed out that the most incident reasons for impairment of oxidative phosphorylation are inhibition of NAD X H-dehydrogenase and protonophoric dissociation of respiration and phosphorylation.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.