Regulation of bradykinin-induced cyclic amp response by quinacrine and prostaglandin E2 and F2 alpha in human synovial fibroblasts.

Bradykinin induces an increment in intracellular cyclic AMP concentrations of human synovial fibroblasts and evokes the release of [3H]arachidonic acid and [3H]-E prostaglandins from human synovial fibroblasts pre-labeled in their phospholipids. Both these bradykinin-induced reactions are inhibited by quinacrine, an inhibitor of phospholipase A activity. The cyclic AMP response of human synovial fibroblasts to bradykinin is potentiated by prostaglandin E2 and inhibited by prostaglandin F2 alpha. These data emphasize the critical role of the prostaglandin system in reactions induced by bradykinin and suggest mechansims by which inflammatory reactions due to bradykinin may be modulated.