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