[The effect of the omega 6/omega 3 PUFA ratios in the rations of rats on the eicosanoid content in the blood plasma and liver].

Purified diets for rats contained 24% fat, with presented with the mixture of sunflower and fish oils whose combination yielded ratios of omega 6 to omega 3 fatty acids equal to 99 0, 49 0, 5 2, 1.9 and 0.12. The alterations in fatty acid composition of blood plasma and the liver were noticed, which manifested in increased omega 3 fatty acid levels in proportion to their dietary content. The elevation of PUFA proportion in the diet increased TBA-reactive substances in the liver. Using radioimmunoassay the levels of PGF2 alpha, TxA2 and PGI2 were determined. The decrease of arachidonic acid as part of tissue lipids caused an inhibition of PGF2 alpha formation in the liver, TxA2 and PGI2 in blood plasma, that showed a possibility of influence the ratio omega 6/omega 3 PUFA in a diet on eicosanoid synthesis by substrate regulation. These results suggest that for characteristics of dietary fat the ratio omega 6/omega 3 PUFA as a criterion reflecting the biological action of two families of essential fatty acids should not be used.