A, reversed phase HPLC separation and profile of products from HUVEC and human PMN coincubations. A, reversed phase HPLC separation and profile of products from HUVEC and human PMN coincubations. Confluent HUVECs were exposed to interleukin-1β for 24 h and treated with 500 μM aspirin (ASA) or vehicle for 20 min at 37°C and 20 μM arachidonic acid for 60 s. Each was incubated with fresh isolated PMNs (HUVEC/PMN cell ratio of 1:50) followed by costimulation with 5 μM ionophore A23187 for 30 min at 37°C. B, UV spectra recorded during the elution of indicated peaks I to IV. Reproduced with permission from the National Academy of Sciences (Claria and Serhan, 1995). Giancarlo Folco, and Robert C. Murphy Pharmacol Rev 2006;58:375-388 The American Society for Pharmacology and Experimental Therapeutics