The effects of antirheumatic drugs on the production of collagenase and tissue inhibitor of metalloproteinases (TIMP) by stimulated rabbit articular chrondrocytes.

Conditioned medium from human peripheral blood mononuclear cells stimulated with concanavalin A (50 micrograms/ml) was used to induce rabbit articular chondrocytes to produce collagenase. In passaged chondrocyte cultures sodium aurothiomalate (GSTM) (either 5 micrograms/ml or 100 micrograms/ml). D-penicillamine (100 micrograms/ml) and dexamethasone (either 100 nM or 200 nM) did not reduce collagenase levels. Chloroquine (0.5 micrograms/ml) had a variable effect. Dexamethasone increased tissue inhibitor of metalloproteinases levels and also reduced collagenase levels in primary chondrocyte and cartilage fragment cultures. When the drugs were added to the mononuclear cells in culture, dexamethasone (10 nM), D-penicillamine (100 micrograms/ml), D-penicillamine (100 micrograms/ml) and copper sulphate (2 micrograms/ml) and chloroquine (5 micrograms/ml) reduced the activity of the conditioned medium when tested onchondrocytes. GSTM (100 micrograms/ml) and chloroquine (0.5 micrograms/ml) had no effect.