THE VITAMIN-E NUTRITIONAL-STATUS OF RATS FED ON DIETS HIGH IN FISH-OIL, LINSEED OIL OR SUNFLOWER SEED OIL

Twelve groups of eight rats and two control groups of sixteen rats wer e given semisynthetic diets with 40% energy as fat for a period of 76 d. All diets contained a minimum of 3% energy as linoleic acid and com parable basal levels of D-alpha- and D-gamma-tocopherol. The diets var ied in fat composition and in the content of DL-alpha-tocopheryl aceta te. The diets high in polyunsaturated fatty acids (PUFA) were either r ich in fish oil (FO; groups 1-4; 10% energy as fish oil PUFA), linseed oil (LN; groups 1-4; 10% energy as alpha-linolenic acid) or sunflower seed oil (SF; groups 1-4; 10 + 3 % energy as linoleic acid). The cont rol groups were given a diet high in monounsaturated fatty acids (MUFA ; CO 1; 10 + 13 % energy as oleic acid) or a diet with an 'average' li noleic acid content (CO 2; 8.5 % energy as linoleic acid). Of each hig h PUFA diet three groups were supplemented with graded levels of DL-al pha-tocopheryl acetate. Steatitis, a sensitive histopathological indic ator of vitamin E deficiency in animals fed on diets rich in fatty aci ds with three or more double bonds, was observed only in the adipose t issue of the FO groups, even in the group with the highest DL-alpha-to copheryl acetate supplementation. Liver and serum alpha-tocopherol lev els were found to be positively correlated and liver and serum gamma-t ocopherol levels negatively correlated with dietary DL-alpha-tocophery l acetate. The groups on the FO diets had significantly reduced liver and serum tocopherol levels in comparison with the groups on the other high-PUFA diets. With the supplementation scheme used for the FO grou ps the liver alpha-tocopherol levels of both control groups were reach ed but the serum control levels were not.