[Current topics in the regulation of prostanoids-1. Inducible cyclooxygenase COX-2 and selective blockers]

Cyclooxygenases (COX) are prostaglandin synthases and are the main therapeutic targets for non-steroidal anti-inflammatory drugs. Recently it has been established that apart from the constitutive isoform, an inducible isoform of this enzyme is upregulated after injurious stimuli. The structures of the genes encoding these enzymes and protein structures have been determined, and with the utilization of knockout mice, the physiological properties of each isozyme are being revealed. COX-1 is responsible for the production of physiological levels of prostanoids, whereas COX-2 is upregulated during inflammatory states and produces prostanoids responsible for the generation of fever, pain or other inflammatory responses. Selective COX-2 blockers may be a safe and useful alternative in the treatment of inflammatory disorders, pain, and fever.