Prostaglandins, thromboxanes, and polymorphonuclear leukocytes: mediation and modulation of inflammation.

When appropriately stimulated (even in the absence of phagocytosis), human polymorphonuclear leukocytes release and/or generate proinflammatory materials and substances capable of provoking tissue injury. These include hydrolases and nonenzymatic substances ordinarily contained within lysosomes, as well as oxygen-derived free radicals. It is now possible to add prostaglandins and thromboxanes to this list. Whereas prostaglandins are capable of eliciting many phenomena associated with inflammation, their effects on cyclic nucleotide metabolism may render these compounds antiinflammatory. Thus, the very cells that release mediators of inflammation provide a mechanism for modulating the inflammatory response.