tellurium and selenocystine

The differences in the effects of inorganic Se (IV and VI) compounds and seleno-cystine [(CySe)2] on the Te (as Na2TeO3) uptake by the yeast, Saccharomyces cerevisiae, has been studied. Se, Te, Ag, Zn, Fe and Co contents of the cells were measured by instrumental neutron activation analysis. For the determination of the Ag content, the monostandard method was applied as the analytical method. The contents of other elements were determined by comparison with standards having similar amounts of the determined element as the sample. Results obtained show that an antagonist interaction occurs between SeO2 and Te. There was a significant increase in the concentrations of Se and Te when the yeast was incubated in the medium containing (CySe)2 and Te. (CySe)2 markedly increased the Ag content of cells, especially within the first 8 h of incubation. The low level of SeO2 in the medium are the exterior factor which produce an observable increase of the Ag concentration in the cells. The higher level of SeO2 in the medium causes a long-term marked increase in the Ag content of the cells. The uptake yield of Ag also increased in the presence of (NH4)2SeO4 in the medium. The Te supply produced a significant enhancement in the Ag content of the cells during the initial 8 h of incubation. The presence of Se and/or Te in the medium causes change in the intracellular Zn, Fe and Co levels.

Topics: Cystine; Metals; Neutron Activation Analysis; Organoselenium Compounds; Saccharomyces cerevisiae; Selenium Compounds; Silver; Tellurium

The effects of sublethal doses of selenite, selenate, selenocystine (Se-Cys) and selenomethionine (Se-Met) as well as of tellurite on body temperature and feeding behavior were examined in male ICR mice. Ten or 30 mumol/kg of chemicals were injected subcutaneously and body temperature was measured up to 4 h. In a separate experiment, the gastric content was weighted 4 h after injection. All chemicals except Se-Met induced both hypothermia and hyperphagia, suggesting that: (a) these two effects are related to each other; (b) among the chemicals tested, Se-Cys appears to be the most potent hypothermia inducer; (c) Se-Met is unique in that it has neither effect.

Topics: Animals; Body Temperature; Cystine; Feeding Behavior; Hyperphagia; Hypothermia; Male; Mice; Organoselenium Compounds; Selenic Acid; Selenious Acid; Selenium; Selenium Compounds; Selenomethionine; Tellurium