Effects of sulphasalazine on prostaglandin inactivation and synthesis in isolated lungs of guinea pig, rat and man.

Sulphasalazine 10(-4M) inhibited PGE2 inactivation in isolated perfused lungs from guinea pig, rat and man and, in guinea pig and rat lungs, inhibited 16,16-dimethyl PGE2 inactivation and accelerated efflux of radioactivity following injection of [14C]PGE2. In rat and human, but not in guinea-pig lung, sulphasalazine inhibited activation of exogenous arachidonate to PG-like substances. Thus sulphasalazine inhibited PG inactivation by inhibiting PG uptake; there was a marked species difference in its effects on arachidonate activation.