The present study was designed to evaluate the effect of anti intercellular adhesion molecule 1(ICAM 1) monoclonal antibody in a rat model of myocardial ischemia reperfusion injury (I/R). Anaesthetized rats were subjected to total occlusion (45 min) of the left main coronary artery followed by 24 h reperfusion. The area of myocardial necrosis, myocardial function (such as LVSP, +P′max, LVEDP and -P′max) and PMN infiltration were measured. We found that the area of myocardial necrosis in treated rats was smaller than that in control group ( P