Cyclooxygenase inhibition prevents PMA-induced increase in pulmonary vascular permeability to albumin.
J Appl Physiol (1985)
; 73(5): 2011-5, 1992 Nov.
Article
em En
| MEDLINE
| ID: mdl-1474079
ABSTRACT
In a previous study, we demonstrated that phorbol myristate acetate-(PMA) induced injury in isolated blood-perfused rabbit lungs was characterized by increased pulmonary vascular resistance (PVR) and permeability to water as measured by fluid filtration coefficient (Kf). The Kf increase was prevented by pretreatment with three cyclooxygenase inhibitors, indomethacin, ibuprofen, and meclofenamate. Other studies have shown that PMA causes a decrease in pulmonary vascular surface area, probably due to the increase in arterial resistance. Measurement of Kf requires increased microvascular pressure, and therefore Kf estimates the permeability of the entire vascular bed. Thus the permeability of the flowing vessels may be overestimated by Kf. In this study, we chose to investigate the effect of PMA on vascular permeability to protein by measuring albumin leak. Because this measurement does not require a hydraulic stress, it is more likely to reflect the permeability of flowing vessels. PMA administration (5 x 10(-8) M) caused significant increases in both PVR and 125I-labeled bovine serum albumin leak. Cyclooxygenase inhibition with indomethacin, ibuprofen, or meclofenamate prevented the PMA-induced increase in albumin leak without affecting the PVR increase. These results suggest that cyclooxygenase-mediated products of arachidonic acid mediate the PMA-induced increase in vascular permeability to both water and protein.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Permeabilidade Capilar
/
Acetato de Tetradecanoilforbol
/
Inibidores de Ciclo-Oxigenase
/
Albuminas
/
Pulmão
Limite:
Animals
Idioma:
En
Revista:
J Appl Physiol (1985)
Assunto da revista:
FISIOLOGIA
Ano de publicação:
1992
Tipo de documento:
Article