Platelet Glycoprotein IIb/IIIa Inhibitor Tirofiban Ameliorates Cardiac Reperfusion Injury

There are many published articles on the effects of the antithrombolytic function of platelet glycoprotein IIb/IIIa inhibitors (GP IIb/IIIa inhibitors) in myocardial infarction. However, few studies have explored the effects and optimal concentration of tirofibans in diminishing the extent of myocardial reperfusion injury (RI). Rats received 120 minutes of coronary ligation and 180 minutes of reperfusion. The rats were then divided into 7 groups based on the concentration of tirofiban administered intravenously 30 minutes prior to coronary reperfusion to the end of reperfusion. The ratio of myocardial necrotic area to area at risk (AAR), and myocardial malondialdehyde (MDA) and plasma myeloperoxidase (MPO) activities were measured. The apoptotic index (AI) was the percentage of myocytes positive for terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling (TUNEL) out of all myocytes stained by 4’, 6-diamidino-2-phenylindole (DAPI). The ratio of myocardial necrotic area to AAR significantly decreased in all tirofiban subgroups. The MDA activity for tirofiban concentrations of 2 and 5 ug/kg/minute showed a slight reduction. MPO activity was significantly decreased at a tirofiban concentration of 2 ug/kg/minute. The AI was significantly decreased at a tirofiban concentration of ≥ 0.4 ug/kg/minute. The results indicate that a tirofiban can significantly ameliorate the cardiac RI and myocyte apoptosis in rats.