title: The inhibition of platelet aggregation by activated macrophages is blocked by dexamethasone.
abstract: The effect of dexamethasone on the ability of activated J774 macrophages to inhibit platelet aggregation was investigated. After 24h incubation with lipopolysaccharide and gamma-interferon, J774 cells generated large amounts of nitric oxide and inhibited platelet aggregation. Incubation of the cells with dexamethasone (0.01-10 microM) caused a concentration-dependent inhibition of both the NO2- production and the anti-aggregating activity of the cells. The inhibitory effect of dexamethasone was blocked by the glucocorticoid antagonist RU 38486. These data suggested that the protective effect of glucocorticoids in endotoxin-induced hypotension and their immunosuppressive action may both depend, at least in part, on the inhibition by these steroids of the induction of the nitric oxide synthase.
authors: Department of Experimental Pharmacology, University of Naples Federico II, Italy.
authors: A
authors: A
authors: Pinto
authors: R
authors: R
authors: Carnuccio
authors: R
authors: R
authors: Sorrentino
authors: M
authors: M
authors: Di Rosa
mesh_terms: D000818:Animals; D002460:Cell Line; D003907:Dexamethasone / Q000494:pharmacology*; D008262:Macrophage Activation / Q000502:physiology; D008264:Macrophages / Q000187:drug effects* / Q000378:metabolism; D008297:Male; D051379:Mice; D009569:Nitric Oxide / Q000378:metabolism*; D010974:Platelet Aggregation / Q000187:drug effects*; D011817:Rabbits; D013917:Thrombin / Q000494:pharmacology
chemical_list: D009569:Nitric Oxide; D003907:Dexamethasone; D013917:Thrombin