“…These products have been detected in carrageenin-induced inflammation (Higgs & Salmon, 1979) and chronic joint inflammation in man (Brodie, Hensby, Parke & Gordon, 1980;Bombardieri, Cattani, Ciabattoni, Di Munno, Pasero, Patrono, Pinca & Pugliese, 1981) but it is not clear from which tissues they are derived. Thromboxane A2 (TXA2) is the major cyclo-oxygenase product in platelets (Hamberg, Svensson & Samuelsson, 1975) and circulating leukocytes (Morley, Bray, Jones, Nugteren & Van Dorp, 1979) whereas vascular endothelial cells produce mainly prostacyclin (Moncada, Gryglewski, Bunting & Vane, 1976).…”