Regulation of prostaglandin synthesis by glucocorticoids.

Glucocorticoids are very effective anti-inflammatory agents since they affect several of the key mediators responsible for the inflammatory response, including prostaglandins. In particular, under normal physiological conditions, prostaglandin synthesis mediated via the constitutively expressed cyclooxygenase-1 (COX-1) is not affected by endogenously or exogenously administered glucocorticoids. However, within the context of the inflammatory response, phospholipase A2 as well as cyclooxygenase-2 (COX-2) are induced, resulting in an exacerbated production of prostaglandins. The antiinflammatory steroids will reduce inflammation-induced prostaglandin synthesis by inhibiting the expression of these two key enzymes, PLA2 and COX-2.