Effect of Dietary Fish Oil on Plasma Thromboxane B2 and 6-Keto-prostaglandin F1α Levels in Septic Rats

• Increased mortality from sepsis is associated with high levels of thromboxane B₂ (TXB₂) and 6-keto-prostaglandin F_1α (PGF_1α). Linoleic acid, an n-6 essential fatty acid, is the usual precursor of TXB₂ and PGF_1α, while fish oil is rich in n-3 essential fatty acid, the precursor of less active moieties. Rats were fed chow, an essential fatty acid–deficient diet, or an essential fatty acid–deficient diet supplemented with linoleic acid or fish oil for 2 weeks. The animals then underwent a sham operation or cecal ligation and puncture to induce sepsis. Six hours later, blood was obtained for analysis. The chow and linoleic acid diets produced significant (twofold to fivefold) increases in levels of both TXB₂ and PGF_1α after sepsis. The essential fatty acid–deficient diet and fish oil diet protected against increases in levels of TXB₂ or PGF_1α during sepsis. Dietary restriction of linoleic acid or fish oil supplementation may play an important role in altering the inflammatory mediator response to sepsis.

(Arch Surg. 1991;126:179-182)