Estrogen protects the heart from ischemia-reperfusion injury via COX-2-derived PGI2.

There is an accumulating body of data to suggest that estrogen mediates its cardioprotective effects via cyclooxygenase activation and synthesis of prostaglandins (PG), specifically PGI2. We hypothesized that inhibition of COX-2 would prevent estrogen's cardioprotective effects after myocardial ischemia-reperfusion. Acute treatment with 17beta-estradiol (E2; 20 microg/rabbit) increased COX-2 protein expression and activity in the myocardium.