[Selective inhibitors of cyclooxygenase-2. New agents against pain and inflammation]

Peripherally active analgesics are considered to exert their effect by blocking the enzyme, cyclo-oxygenase (COX), thus inhibiting the biosynthesis both of prostaglandins and of thromboxanes. It was recently found that there are two enzymes which can form prostaglandins: COX-1 and COX-2. Whereas COX-1 is normally expressed in many tissues, expression of COX-2 can be induced in response to inflammation. New experimental findings in 'knockout' mice have suggested that subgrouping of cyclo-oxygenases as 'good' (COC-1) and 'bad' (COX-2) may be inappropriate. COX-2 specific NSAIDs (non-steroidal anti-inflammatory drugs) may be potent antiinflammatory and analgesic agents with no serious side-effects, though this has yet to be confirmed in clinical trials.