Effect of disease modifying antirheumatic drugs and nonsteroidal antiinflammatory drugs upon cellular and fibronectin responses in a pleurisy model.

Intrapleural injections of carrageenan into rats resulted in peak increases in intrapleural inflammatory cell counts (90% mononuclear cells) and fibronectin content at 3 days after the injections. Administration of disease modifying antirheumatic drugs (DMARD) prevented the increases in both fibronectin levels and intrapleural cell counts, whereas nonsteroidal antiinflammatory drugs, in general, potentiated the increases. Inhibition of fibronectin production by DMARD in carrageenan induced pleurisy in rats may be related to the antirheumatic activity of this class of drugs.