Effects of antiinflammatory drugs on the release from porcine synovial tissue in vitro of interleukin 1 like cartilage degrading activity.

The effects were studied of antiinflammatory drugs possessing inhibitory effects on (a) cyclooxygenase (CO), (b) cyclooxygenase plus 5-lipoxygenase (CO-LO), (c) 5-lipoxygenase (5-LO) and (d) phospholipase A2 (PLA2) activities, for their actions on the release from porcine synovial tissue in culture of cartilage-degrading ("catabolin" or interleukin-1 like) activity (= CDA). CDA was reduced by CO inhibitors, enhanced by CO-LO and PLA2 inhibitors, and unaffected by 5-LO inhibitors. These results suggest that (a) antiinflammatory drugs may affect synovial production of CDA ascribable to IL-1, according to their properties as inhibitors of arachidonate metabolism, and (b) products of arachidonic acid metabolism may influence production of synovial CDA.