Effects of variable linoleate intake on aortic PGI2-like activity and fatty acid composition: difference between rat...

Two animal species, the laboratory rat and a non-human primate (the common marmoset) were compared with respect to the influence of dietary lipid supplementation on both fatty acid composition and prostanoid synthetic capacity of aorta. Standard chow (REF. diet) was supplemented (12% w/w) with either sheep fat (SF) or sunflower seed oil (SSO). Differences were apparent in the aortic phospholipid fatty acids from both animal models, as a result of the diet, although the type and the extent of changes displayed a considerable species variation. For example, after the SSO diet, the proportion of linoleic acid in rat aorta displayed only a modest increase whilst in marmosets it was doubled. No change was apparent in the proportion of arachidonic acid in rats, whereas the marmosets showed a reduction (P less than 0.05) with both lipid supplements. Rats fed the SF diet showed a considerable increase in aortic PGI2-like activity compared to REF. And SSO supplemented groups. In contrast, no dietary induced changes were observed in the aorta from marmosets despite compositional changes. The results indicate no direct association between the synthesis of PGI2-like activity and membrane lipids and demonstrate the need for careful selection of the proper animal model, particularly in nutritionally orientated experiments.