Protective role of intracoronary fatty acid binding protein in ischemic and reperfused myocardium

In this study, fatty acid binding protein was used to protect an ischemic heart from reperfusion injury. Isolated rat heart was preperfused in the presence of 1.4 microM liposome-bound fatty acid binding protein for 15 minutes, followed by 30 minutes of ischemia and 30 minutes of reperfusion. Our results indicated better preservation of myocardial high-energy phosphate compounds (including ATP and creatine phosphate), reduced creatine kinase and lactate dehydrogenase release from the heart, and improved coronary flow in hearts treated with fatty acid binding protein compared with untreated controls. Fatty acid binding protein enhanced reacylation of arachidonic acid into phospholipids, thereby preserving membrane phospholipids and reducing free fatty acid contents during ischemia and reperfusion. In addition, fatty acid binding protein-bound long-chain free fatty acids and their thioesters as well as carnitine esters were increased in the cytosolic compartment of the heart. These results suggest that fatty acid binding protein may be used as a possible therapeutic agent to improve myocardial function during reperfusion of ischemic heart.