Effect of diclofenac on prostaglandin E and hyaluronic acid production by human synovial fibroblasts stimulated with interleukin-1.

Cultured human synovial fibroblasts were stimulated with human recombinant interleukin 1 beta to overproduce prostaglandin E (PGE) and hyaluronic acid (HA). Diclofenac, indomethacin and hydrocortisone inhibited stimulation of PGE production. Half-maximal inhibition occurred at 1.10 x 10(-9), 2.79 x 10(-8) and at 5.52 x 10(-8) M, respectively. Diclofenac or indomethacin had no effect on HA production, while hydrocortisone had an inhibitory effect (half-maximal inhibition at 2.76 x 10(-7) M). This model could be a useful in vitro indicator for the in vivo pharmacological actions of anti-inflammatory drugs.