TREATMENT OF CARRAGEENAN-INDUCED ARTHRITIS BY THE PLATELET-ACTIVATING-FACTOR ANTAGONIST BN-50730

Objective-To evaluate the role of platelet activating factor (PAF) in the early stage of arthritis. Methods-Arthritis was induced in rabbits by weekly intra-articular injections of carrageenan. A PAF receptor a ntagonist, BN 50730, was used as a preventive or curative agent. Resul ts-BN 50730 was able partially to prevent the development of arthritis , and was also active on established arthritis. The joint arthritis sc ores of BN treated animals were significantly lower than those of the non-treated animals. The blood concentrations of PAF, PAF bound to lip oproteins (lipo-PAF), and its precursor, lyso-PAF, were not correlated with clinical variations. Conclusions-The present data demonstrate a therapeutic action of a PAF antagonist in experimental arthritis and s uggest a critical role for PAF during the early stage of arthritis.