RP-54745, a potential antirheumatic compound. Inhibitor of macrophage stimulation and interleukin-1 production.

1.5*10^6 peritoneal murine macrophages, after a 2-h period of adherence, were cultured in RPMI 1640 with 5% FCS for 20 h at 37 ℃ in 5% CO2.?In vitro, test compounds were added 15 min before the stimulant, 100ng/ml LPS, and the cells were incubated for 2-24 h. In vivo, thioglycollate-stimulated female OFt mice were orally treated with 5 or 25 mg/kg/day RP 54745 for 4 days.?Harvested macrophages were then stimulated ex vivo for 2 h with LPS at concentrations ranging from 0.1-10 ng/ml.?In some assays, 4 h before macrophage harvesting, mice were treated intraperitoneally with LPS: 0.5 ug per mouse.?At the end of the in vitro incubation period, supernatants were removed from cultures, and cells were lysed by three freeze/thaw cycles.?Both extracellular and cell-associated IL-1 activities were assayed.