ABSTRACT
In the present study the bioavailability of selenium in Se-yeast was compared with that in sodium selenite to rats fed on low-Se diet from a keshan discaes area. The bioavailability of selenium in Se-yeast when estimated by heart, liver kidney and erythrocyte Se contents was significantly greater than that in selenite at wk 2 and 4 of supplement, indicating that selenium in Se-yeast is more cfficiently retained in tissues than selenite selenium. When the criterion used was either platelet or liver glutathione peroxidase (GSH_(?)) activity, the bioavailability was lower for selenium in Se-yeast than for in selenite at wk 2, but higher at wk 4, showing that selenium from both selenite and Se-yeast is clearly available for GSH_(?), synthesis, "although Se-yeast restores GSH_(?) activity more slowly. In addition, the effect of selenium in Se-yeast in maintaining cither Se levels in heart and erythrocyte or GSH_(?) activities in platelets and liver was superior to that of selenite after the selenium supplements were withdrawn.