Dexamethasone inhibits leukocyte emigration in rat mesenteric post-capillary venules: an intravital microscopy study.
J Leukoc Biol
; 62(3): 301-8, 1997 Sep.
Article
em En
| MEDLINE
| ID: mdl-9307068
ABSTRACT
The effect of subcutaneous administration of dexamethasone (DEX) on interleukin-1beta(IL-1beta, 20 ng i.p., - 2 h) and platelet-activating factor (PAF, 100 nM in superfusion) -induced leukocyte interaction with the endothelium of rat mesenteric post-capillary venules was studied. DEX produced a dose-dependent inhibition of IL-1beta-induced leukocyte extravasation in the rat mesenteric vascular bed, with a calculated ED5o of 40 microg/kg and a maximal effect of 80-100% inhibition at 0.1 mg/kg. IL-1beta-induced cell adhesion to post-capillary venules was only partially inhibited by the steroid, with a calculated ED50 of 480 microg/kg and a maximal effect of 40-60% inhibition. Furthermore, the steroid inhibited leukocyte emigration, but not adhesion, caused by superfusion of the mesenteric vascular bed with PAF. A doubling of leukocyte emigration time (from 226 to 552 s) was observed after treatment of rats with DEX. Administration for 5 days of a dose of 10 microg/kg DEX (which was inactive when given as a single injection) resulted again in a selective inhibition of IL-1beta-induced leukocyte emigration, without effect on cell adhesion. These data demonstrate a preferential susceptibility of the leukocyte emigration process to the inhibitory action of DEX.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Circulação Esplâncnica
/
Dexametasona
/
Fator de Ativação de Plaquetas
/
Movimento Celular
/
Glucocorticoides
/
Leucócitos
Limite:
Animals
Idioma:
En
Revista:
J Leukoc Biol
Ano de publicação:
1997
Tipo de documento:
Article
País de afiliação:
Reino Unido