Reduced inflammatory response in rats fed fat-rich diets: Role of leukotrienes

• Published in: Life sciences (1973) 2000-05, Vol.67 (1), p.13-21
• Main Authors: Lopes, Lúcia R., Jancar, Sônia, Curi, Rui, Sannomiya, Paulina
• Format: Article
• Language: English
• Subjects: Acute-Phase Reaction - chemically induced; Acute-Phase Reaction - diet therapy; Acute-Phase Reaction - metabolism; Animals; Capillary Permeability - drug effects; Carrageenan; Coconut Oil; Dietary Fats - administration & dosage; Dinoprostone - metabolism; Edema - chemically induced; Edema - metabolism; Enzyme-Linked Immunosorbent Assay; Exudates and Transudates - metabolism; Fat-rich diets; Hindlimb - drug effects; Inflammatory response; Leukotriene Antagonists - pharmacology; Leukotriene C4 - metabolism; Leukotriene D4 - metabolism; Leukotrienes; Male; Plant Oils - administration & dosage; Pleural Effusion - metabolism; Pleurisy - chemically induced; Pleurisy - metabolism; Propionates - pharmacology; Quinolines - pharmacology; Rats; Rats, Wistar; Skin - blood supply; Skin - drug effects; Soybean Oil - administration & dosage
• ISSN: 0024-3205; 1879-0631
• DOI: 10.1016/S0024-3205(00)00597-X

The effect of fat-rich diets on the acute inflammatory response was examined. Male Wistar rats aged 21 days were fed, for 6 weeks, with a control diet (4% fat content), or a control diet supplemented with coconut or soybean oils (15% fat content). Carrageenan-induced paw oedema and pleurisy were evaluated. Prostaglandin (PG) E 2 and leukotriene (LT) C 4/D 4 concentrations were determined in the pleural exudate (ELISA). Pleural samples were tested for their effect on cutaneous vascular permeability of control rats and the effect of a LTD 4 receptor antagonist (L660-711; 10 mg/kg; i.v.) examined. Relative to controls, rats fed both fat-rich diets presented a significant reduction in protein leakage and oedema formation without affecting the number of migrating leukocytes. Production of LTC 4/D 4 in pleural exudate was significantly increased from 1.8 ± 0.2 ng/ml in controls to 2.8 ± 0.2 and 3.0 ± 0.3 ng/ml in animals fed coconut and soybean oil enriched diets, respectively, without changes in PGE 2 production. The activity of these samples on cutaneous vascular permeability was 50% reduced, returning to control values after treatment of testing animals with a LTD 4 receptor antagonist. Rats fed fat-rich diets presented a reduced inflammatory response due, at least in part, to the LTC 4/D 4 mediated vasoconstrictor effect.