A single administration of fish oil inhibits the acute inflammatory response in rats.

OBJECTIVE: To investigate the antiinflammatory effects of a single administration of fish oil (FO) on the acute inflammatory response.

METHODS: The paw edema and pleurisy models were used to evaluate the effects of FO dissolved in olive oil (FOP) orally administered in a single dose in rats. Nitric oxide (NO) concentrations in the pleural exudate were performed according to the Griess method and the cytokine concentrations were determined by Luminex bead-based multiplex assay.

RESULTS: FOP treatment (30 and 300 mg/kg) significantly reduced paw edema. FOP treatment at 18.75, 37.5, 75.0, 150.0, and 300 mg/kg decreased both the volume of pleural exudate and cellular migration into the pleural cavity and each of these doses presented the same effectiveness. Treatment with FOP (300 mg/kg) reduced NO, TNF-α, IL-1β, and IL-6 concentrations in the pleural exudate.

CONCLUSIONS: The present data provide evidence that FO has inhibitory effects on the acute inflammatory response when administered in a single dose in rats. This effect might be attributable to a direct inhibitory effect of FO on the production or release of inflammatory mediators that are involved in the pathological processes evaluated herein.