QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Purchase Article View Shopping Cart Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Salbe, A. D. Articles by Levander, O. A. Search for Related Content PubMed PubMed Citation Articles by Salbe, A. D. Articles by Levander, O. A.

Comparative Toxicity and Tissue Retention of Selenium in Methionine-Deficient Rats Fed Sodium Selenate or L-Selenomethionine^1,2,

U.S. Department of Agriculture, Human Nutrition Research Center, Vitamin and Mineral Nutrition Laboratory, Beltsville, MD 20705

Selenium (Se) toxicity is known to be affected by level of intake of the mineral, but there are conflicting reports on the relative toxicities of the various chemical forms of Se. We monitored Se toxicity in rats fed Torula yeast-based diets containing 0.1, 0.5 or 2.5 µg Se/g of diet as either sodium selenate (Na₂SeO₄) or L-selenomethionine (SeMet). Half the diets were supplemented to contain adequate dietary methionine (Met). Weights were monitored weekly for 6 (Met-adequate) or 7 (Met-deficient) wk, at which time the rats were killed. There were no significant differences in final weight among Met-adequate rats, regardless of level or form of dietary Se. Methionine-deficient rats all gained significantly less weight than their Met-adequate counterparts. Selenosis was most severe in the Met-deficient rats fed 2.5 µg Se/g of diet as Na₂SeO₄, as indicated by significantly impaired weight gains. Nonetheless, Se retention in serum, heart, brain, bone, testes, colon, skin, lungs and pancreas was greater in rats fed SeMet than in those fed Na₂SeO₄, and Met deficiency further intensified this trend. The kidney was the only organ in which Se levels were markedly higher in the severely poisoned Met-deficient rats fed Na₂SeO₄. Further research is needed to determine whether elevated kidney Se levels are related to the greater toxicity observed in the Met-deficient rats fed Na₂SeO₄.

KEY WORDS: • selenium toxicity • L-selenomethionine • selenate • rats

¹ Supported in part by National Cancer Institute Interagency Agreement No. Y01-CN-40620.

² Preliminary reports of this research were presented at the 28th Annual Meeting of the American Society for Clinical Nutrition, Washington, D.C., April 28–30, 1988. [BAKER, D. A., LOCKLEAR, F. A., SALBE, A. D. & LEVANDER, O. A. (1988) Effect of dietary methionine (Met) on selenium (Se) retention by rats in tissues of concern in human disease. Am. J. Clin. Nutr. 47: 781; MALONEY, G. D., SALBE, A. D. & LEVANDER, O. A. (1988) Selenium (Se) as sodium selenate is more toxic than Se as L-selenomethionine in methionine deficient rats. Am. J. Clin. Nutr. 47: 782].

³ To whom reprint requests should be addressed.

Manuscript received 3 July 1989. Revision accepted 8 November 1989.