Influence of excess vitamin E on vitamin A toxicity in rats.
Male Holtzman rats (78 g) were fed semipurified 16% protein diets for 8 weeks using a food grade soy protein concentrate as the protein source. The basal diet (A) contained added DL-methionine (0.26%) and adequate amounts of vitamins A (14,535 IU/kg as retinyl acetate) and E (60 IU/kg as DL-alpha-tocopheryl acetate) and all other required nutrients. Experimental diets included: (B) basal plus 600 IU of vitamin E/kg; (C) basal plus 6,000 IU of vitamin E/kg; (D) basal plus 2.9 X 10(6) IU of vitamin A/kg; (E) basal plus 2.9 X 10(6) IU of vitamin A plus 600 IU of vitamin E/kg; and (F) basal plus 2.9 X 10(6) IU of vitamin A plus 6,000 IU of vitamin E/kg. Both vitamin A and vitamin E had a significant (P less than 0.05) effect on growth. There was an increase in growth with vitamin E intake and a decrease in growth with vitamin A intake. The net result of these two effects was that the groups fed both vitamins tended to be quite close in mean values to the group fed only the basal diet. Vitamin A significantly (P less than 0.05) increased relative weights of spleen and testes; vitamin E reduced that effect. Vitamin E also significantly (P less than 0.05) reduced relative adrenal weight whereas vitamin A significantly increased it. The two effects tend to cancel each other in the sense that the group fed both vitamins had an average relative adrenal weight quite close to that of the group fed only the basal diet. However, vitamin A still had an effect even when 6,000 IU of vitamin E was fed. The interaction effect of the two vitamins was significant (P less than 0.05) for plasma total protein and liver vitamin A. There was an increase in liver vitamin A with increasing levels of vitamin E in the diet. Blood urea nitrogen and plasma cholesterol were unchanged. A significant interaction of vitamins A and E was found to effect plasma total protein, liver vitamin A, and relative weight of spleen and testes.
D000818:Animals; D001798:Blood Proteins / Q000378:metabolism; D001835:Body Weight / Q000187:drug effects; D004032:Diet; D004044:Dietary Proteins / Q000008:administration & dosage; D066298:In Vitro Techniques; D050356:Lipid Metabolism; D008099:Liver / Q000378:metabolism; D008297:Male; D009584:Nitrogen / Q000378:metabolism; D009929:Organ Size; D014674:Plant Proteins, Dietary / Q000008:administration & dosage; D051381:Rats; D013025:Glycine max; D014801:Vitamin A / Q000378:metabolism / Q000633:toxicity*; D014810:Vitamin E / Q000009:adverse effects*
D001798:Blood Proteins; D004044:Dietary Proteins; D014674:Plant Proteins, Dietary; D014801:Vitamin A; D014810:Vitamin E; D009584:Nitrogen