Oleic acid lung injury in sheep

Abstract

Intravenous infusion of oleic acid into experimental animals causes acute lung injury resulting in pulmonary edema. We investigated the mechanism of oleic acid lung injury in sheep. In experiments with anesthetized and unanesthetized sheep with lung lymph fistulas, we measured pulmonary arterial and left atrial pressures, cardiac output, lung lymph flow, and lymph and plasma protein concentrations. We injured the lungs with intravenous infusions of oleic acid at doses ranging from 0.015 to 0.120 ml/kg. We found that oleic acid caused reproducible dose-related increases in pulmonary arterial pressure and pulmonary vascular resistance, arterial hypoxemia, and increased protein-rich lung lymph flow and extravascular lung water. The lung fluid balance changes were characteristic of increased permeability pulmonary edema. Infusion of the esterified fat triolein had no hemodynamic or lung fluid balance effects. Depletion of leukocytes with a nitrogen mustard or platelets with an antiplatelet serum had no effect on oleic acid lung injury. Treatment of sheep before injury with methylprednisolone 30 mg/kg or ibuprofen 12.5-15.0 mg/kg also had no effects. Unlike other well-characterized sheep lung injuries, injury caused by oleic acid does not require participation of leukocytes.

Differential Distribution of Lipid Microemboli After Cardiac Surgery

“…Another explanation could be a toxic reaction. It has been shown that oleic acid, when given intravenously to test animals, causes lung injury with edema and severe hypoxemia (13). In addition, it has been shown that uncharged fat (such as triglycerides) and also free fatty acids have toxic properties.…”

Divergent Effects of Neutrophils on Fas-Induced Pulmonary Inflammation, Apoptosis, and Lung Damage

“…Reperfusion-, immune complex-, sepsis-, or even LPS-induced forms of acute lung injury responded with a reduction of lung damage parameters after previous neutrophil depletion. However, for example oleic acid-or hyperoxiainduced ALI did not respond favourable to previous PMN depletion [89,122,176].…”

Estabilidade do modelo animal de lesão pulmonar aguda induzida por ácido oleico

“…(6) Venous infusion of OA causes capillary endothelial injury, (7) has little effect on the relaxation/ contraction properties of the endothelium, (8) respects gravity-dependent areas (9) and is dose-dependent. (10) Gas exchange is known to worsen, although there is controversy regarding how long it takes the physiological variables to stabilize after OA administration. (11)(12)(13)(14) Depending on the dose used, it is possible to keep the animal alive for up to seven days, although the evolution of the biological variables is debatable.…”