Cox-1 (cyclooxygenase-1)

This protein acts as an enzyme and specifically catalyzes (speeds) the production of certain chemical messengers (called prostaglandins). The prostaglandins work within certain cells responsible for inflammation and other functions. In the stomach, for example, they promote the production of the natural mucus lining which protects the inner stomach. Because the common antiinflammatory drugs (like aspirin, ibuprofen and naproxen) block the action of Cox-1, they can reduce inflammation, but they can also decrease the natural stomach protective mucus lining and lead to stomach upset, intestinal bleeding, and ulcers.