Effect of indomethacin on collagen biosynthesis by rabbit articular chondrocytes in monolayer cultures

The influence of indomethacin on collagen biosynthesis in rabbit articular chondrocyte monolayer cultures was studied. Two applications within the space of three days of therapeutic doses (10(-5) or 10(-6)M), as well as repeated applications four days running of lower doses (10(-8) or 10(-10)M), increased the biosynthesis of both collagen and non-collagen proteins. Two applications of higher doses (10(-3) or 10(-4M) decreased DNA synthesis and inhibited both collagen and non-collagen protein biosynthesis. These results might well be considered in connection with the adverse reactions observed in some patients with long-term use of indomethacin.