Effect of dietary nucleotides on the fatty acid composition of rat liver microsomes

Department of Biochemistry and Molecular Biology, University of Granada, Granata, Andalusia, Spain
Archives internationales de physiologie, de biochimie et de biophysique 03/1993; 101(2):123-8. DOI: 10.3109/13813459309008880
Source: PubMed


The present study was designed to evaluate the influence of dietary nucleotides on the lipid composition of liver microsomes in weanling rats. Rats at weaning were fed, one group with a semipurified nucleotide-free diet and three groups with the same diet supplemented with three different levels of each of the nucleotides AMP, GMP, IMP, UMP and CMP, during 4 weeks. Long chain polyunsaturated fatty acids of the n-6 and n-3 series were increased in phospholipids of liver microsomes for rats fed the nucleotide supplemented diets; however, the cholesterol/phospholipid phosphorus ratio was maintained fairly constant. The results obtained suggest that dietary nucleotides modify the polyunsaturated fatty acid metabolism through a lower rat liver delta-9 desaturase activity and through increased activities of delta-5 and delta-4 desaturases.

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