caa a22 4500 386322112 CHVBK 20180307111630.0 cr unu---uuuuu 161130e198807 xx s 000 0 eng 10.1079/BJN19880076 doi S0007114588000777 pii (NATIONALLICENCE)cambridge-10.1079/BJN19880076 Effect of dietary methionine on tissue selenium and glutathione peroxidase (EC 1.11.1.9) activity in rats given selenomethionine [Elektronische Daten] 1. The effect of dietary methionine on the utilization of selenium from dietary selenomethionine ([Se]Met) for tissue Se deposition and for glutathione peroxidase (EC 1.11.1.9; GSH-Px) synthesis was studied in male weanling rats. 2. When rats were given 0.5 mg Se as [Se]Met/kg diet supplemented with 0, 4 or 9 g methionine/kg, Se in plasma, erythrocytes, liver and muscle increased significantly over the 20 d period for all methionine-treatment groups. The increases in erythrocyte and muscle Se, however, were significantly higher in rats fed on the methionine-deficient diet compared with the methionine-supplemented diets. 3. In contrast to the increases in tissue Se, GSH-Px activity in liver, plasma and muscle decreased in methionine-deficient rats given 0.5 mg Se as [Se]Met/kg whereas GSH-Px activity was maintained or increased in rats supplemented with methionine. 4. The percentage of tissue Se associated with GSH-Px was calculated from the measured Se concentration and GSH-Px activity. A significantly lower percentage of Se was associated with GSH-Px in methionine-deficient rats compared with methionine-supplemented rats. 5. These results show that Se from dietary [Se]Met is preferentially incorporated into body proteins rather than used for GSH-Px synthesis when methionine is limiting in the diet. 6. These results further suggest that [Se]Met might not be the optimum Se compound to use for Se supplementation because metabolism of dietary [Se]Met to a biochemically active form, such as GSH-Px, was impaired when [Se]Met was provided in diets low in methionine. Copyright © The Nutrition Society 1988 Waschulewski Ingo H. Department of Nutrition and Food Science, and Nutritional Sciences Program, University of Arizona, Tucson, AZ 85721, USA Sunde Roger A. Department of Nutrition and Food Science, and Nutritional Sciences Program, University of Arizona, Tucson, AZ 85721, USA British Journal of Nutrition Cambridge University Press 60/1(1988-07), 57-68 0007-1145 60:1<57 1988 60 BJN https://doi.org/10.1079/BJN19880076 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1079/BJN19880076 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Waschulewski Ingo H. Department of Nutrition and Food Science, and Nutritional Sciences Program, University of Arizona, Tucson, AZ 85721, USA NATIONALLICENCE 700 1- Sunde Roger A. Department of Nutrition and Food Science, and Nutritional Sciences Program, University of Arizona, Tucson, AZ 85721, USA NATIONALLICENCE 773 0- British Journal of Nutrition Cambridge University Press 60/1(1988-07), 57-68 0007-1145 60:1<57 1988 60 BJN CC0 http://creativecommons.org/publicdomain/zero/1.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-cambridge