Suppression by dexamethasone of vascular permeability responses induced with leukotrienes C and D in the rat skin.
The present experiment was designed to investigate whether glucocorticoids counteract proinflammatory action of leukotrienes C and D which were suggested to play an important role as mediators in the inflammatory exudate response. Vascular permeability was measured using 131I-labeled human serum albumin (131I-HSA) as a tracer. The vascular permeability was elevated promptly after intradermal injection of chemically synthesized leukotriene C or D and then rapidly fell down to the control level. A positive dose-response relationship was observed in the dose levels of 0.01-1 microgram of leukotrienes. Dexamethasone at doses of 0.15, 0.5 and 1.5 mg/kg caused dose-dependent suppression of vascular permeability response induced with leukotrienes C and D. The present data indicate that glucocorticoids are capable of exerting direct inhibitory effect against proinflammatory action of leukotrienes C and D produced through phospholipase A2-arachidonate-lipoxygenase pathway.
D000818:Animals; D001095:Arachidonic Acids / Q000494:pharmacology*; D002199:Capillary Permeability / Q000187:drug effects*; D003907:Dexamethasone / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D008297:Male; D051381:Rats; D013189:SRS-A / Q000378:metabolism* / Q000494:pharmacology*; D012867:Skin / Q000098:blood supply
D001095:Arachidonic Acids; D013189:SRS-A; D003907:Dexamethasone