Abstract: In order to investigate the effect of different ALA levels of oils on fatty acid metabolism of rats fed with high fat diet,rats were divided into control (Cont) group,high fat diet (HFD) group,peanut oil (PO) group,13%,27% and 55% α-linolenic acid blend oil (ALA-BO) groups.Besides Cont and HFD groups,other rats were fed with high-fat diet and treated simultaneously with corresponding oils (2 ml/kg.bw) orally for 6 weeks.The total fatty acid composition in plasma,liver,brain,kidney and heart were determined.The results showed that high fat diet could reduce the n-3 PUFA levels in all tissues,but increasing ALA intake could result in an incorporation of n-3 PUFA in tissues and also showed a dose-effect relationship.There were some tissue-dependent differences in the increase of n-3 PUFA levels,the increase of ALA in kidney and heart was greater than that in plasma,brain and liver,and the EPA level in brain and liver enhanced significantly,but no change was observed in DPA level in kidney and heart,and there was no significant change in DHA level in tissues.No difference was revealed in C18:3 (n-6) and C20:3 (n-6) levels among 13%,27% and 55% ALA-BO groups,but C20:4 level decreased significantly in plasma,brain and kidney when compared with PO group.Our data suggestted that oils rich in ALA could increase the levels of ALA and its metabolites in rat tissues and improve the relative proportion of EPA and DPA in brain,which may be one mechanism of ALA in reducing the risk of cardiovascular disease and promoting the growth of brain.

Key words: α-linolenic acid, high-fat diet, rat, fatty acid metabolism