* * *
cy·clo·ox·y·gen·ase .sī-klō-'äk-si-jə-.nās, -äk-'sij-ə-, -.nāz n an enzyme that catalyzes the conversion of arachidonic acid to prostaglandins, that is inactivated by aspirin and other NSAIDs, and that has two isoforms of which one is involved in the cascade of events producing the pain and inflammation of arthritis and the other is not see COX-1, COX-2
* * *
cy·clo·oxy·gen·ase (COX) (si″klo-okґsə-jən-ās) an activity of prostaglandin-endoperoxide synthase (q.v.). There are two isoforms, called cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2). COX-1 is involved in the synthesis of prostaglandins that maintain the integrity of the gastrointestinal mucosa. COX-2 is made primarily in response to injury or inflammation and is involved in the synthesis of prostaglandins involved in inflammation and the immune response. See also COX-2 inhibitor, under inhibitor.Medical dictionary. 2011.