Methylprednisolone Prevention of Increased Lung Vascular Permeability following Endotoxemia in Sheep
AUTOR(ES)
Brigham, Kenneth L.
RESUMO
To see whether methylprednisolone would affect the pulmonary vascular response to endotoxemia, we studied responses to endotoxemia in the presence and absence of methylprednisolone in the same chronically instrumented, unanesthetized sheep. Infusion of Escherichia coli endotoxin (0.70-1.33 μg/kg) caused an initial period of marked pulmonary hypertension followed several hours later by a long period of increased vascular permeability when pulmonary vascular pressures were near base line (base-line pulmonary artery pressure (PPa) = 21±1 cm H2O SE, left atrial pressure (Pla) = 1±3; experimental PPa = 20±3, Pla = 3±4; P = NS), lung lymph flow (˙Qlym) was high (base-line ˙Qlym = 7.2±0.2 ml/h; experimental ˙Qlym = 23.2±1.0; P < 0.05) and lymph/plasma protein concentration (L/P) was high (base-line L/P = 0.65±0.04; experimental L/P = 0.79±0.05; P < 0.05). When methylprednisolone (1.0 g + 0.5 g/h i.v.) was begun 30 min before the same dose of endotoxin was infused, the initial pulmonary hypertension was less and the late phase increase in lung vascular permeability was prevented (experimental PPa = 24±1, Pla = 1±1, ˙Qlym = 10.0±0.4; L/P = 0.56±0.03). ˙Qlym and L/P were significantly (P < 0.05) lower than with endotoxin alone. Methylprednisolone began during the initial pulmonary hypertensive response to endotoxin also prevented the late phase increase in lung vascular permeability, but the drug had no effect once vascular permeability was increased. We conclude that large doses of methylprednisolone given before or soon after endotoxemia prevent the increase in lung vascular permeability that endotoxin causes, but do not reverse the abnormality once it occurs.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=370670Documentos Relacionados
- Prevention by granulocyte depletion of increased vascular permeability of sheep lung following endotoxemia.
- Increased Sheep Lung Vascular Permeability Caused by Pseudomonas Bacteremia
- Effects of antihistamines on the lung vascular response to histamine in unanesthetized sheep. Diphenhydramine prevention of pulmonary edema and increased permeability.
- Effect of OKY 046, a thromboxane synthase inhibitor, on lung vascular permeability after pulmonary embolism in sheep.
- Activation of adherent vascular neutrophils in the lung during acute endotoxemia