system
Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, METHODS, RESULTS. Meshes: Acute Disease, Animals, Apoptosis, Coronary Stenosis, Coronary Vessels, Cyclooxygenase 2 Inhibitors, Disease Models, Animal, Echocardiography, Injections, Intraperitoneal, Isoxazoles, Ligation, Male, Mice, Myocardial Infarction, Myocardial Reperfusion Injury, Myocardium, Ventricular Remodeling.
user
Does parecoxib inhibit apoptosis in acute myocardial infarction due to permanent coronary ligation but not due to ischemia-reperfusion? Context: Myocardial ischemia induces cyclooxygenase 2 (COX-2) expression. We evaluated the effects of parecoxib, a COX-2 inhibitor, in 2 different mouse models of myocardial ischemia: permanent left coronary artery ligation (PI) and transient ligation (30 minutes ischemia) followed by reperfusion (I/R). Forty adult male Institute of Cancer Research mice underwent PI (n = 24) or I/R (n = 16), followed by randomization to parecoxib (0.75 mg/kg intraperitoneal daily) or normal saline for 7 days. Parecoxib significantly reduced apoptosis [0.8% vs. 3.4% (saline), P < 0.001] and 7-day mortality [0% vs. 57% (saline), P = 0.040] in the PI group but showed no benefit in the I/R group. Parecoxib-treated mice also exhibited greater fractional shortening in the PI group [22% vs. 14% (saline), P = 0.045) but not in the I/R group. Parecoxib did not affect infarct size in either group.
assistant
COX-2 may play a pivotal role in mediating apoptosis in the ischemic peri-infarct myocardium that is not reperfused after infarct. Final Decision: yes