Triolein increases microvascular permeability in isolated perfused rabbit lungs: role of neutrophils.
BACKGROUND
Pathophysiologic mechanisms of the fat embolism syndrome are poorly understood. Neutrophils are thought to play a role in the development of many forms of acute lung injury. The objective of this study was to examine the role of intrapulmonary neutrophils in lung injury resulting from fat infusion.


METHODS
Triolein (0.08 mL/kg) was infused into isolated rabbit lungs perfused with Krebs-Henseleit buffer. Pulmonary arterial pressure was monitored, and pulmonary vascular resistance and microvascular permeability (Kf) were measured at baseline and 60 minutes after triolein infusion.


RESULTS
Triolein produced increases in pulmonary arterial pressure, pulmonary vascular resistance, and Kf. Neutrophil depletion or inhibition of neutrophil elastase prevented the increase in Kf after triolein, and catalase partially blocked this Kf increase.


CONCLUSIONS
These results suggest that activated intrapulmonary neutrophils play a major role in developing triolein-induced lung injury, intrapulmonary neutrophils act chiefly via neutrophil elastase release, and reactive oxygen species are involved in the lung injury.
Nakata
Y
Y
Department of Anesthesiology, St. Louis University School of Medicine, Missouri 63110-0250, USA.
Dahms
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TE
D000818:Animals; D001794:Blood Pressure; D002199:Capillary Permeability / Q000187:drug effects; D004195:Disease Models, Animal; D004620:Embolism, Fat / Q000150:complications / Q000503:physiopathology*; D006439:Hemodynamics; D008168:Lung / Q000098:blood supply* / Q000187:drug effects / Q000378:metabolism; D008833:Microcirculation; D009504:Neutrophils / Q000502:physiology*; D009195:Peroxidase / Q000378:metabolism; D011817:Rabbits; D012128:Respiratory Distress Syndrome / Q000209:etiology / Q000503:physiopathology*; D014304:Triolein / Q000494:pharmacology*; D014655:Vascular Resistance
D014304:Triolein; D009195:Peroxidase