BACKGROUND: Ischemic preconditioning (IPC) and propofol has been demonstrated to inhibit postischemic adhesion of PMNs on coronary vascular endothelium, respectively. The purpose of this study is to investigate whether IPC and propofol inhibit postischemic coronary vascular adhesion of PMNs synergistically.

METHODS: Twenty-eight isolated rat hearts were subjected to stabilization for 15 min, perfusion for 15 min, global ischemia for 15 min and reperfusion for 60 min serially. The isolated hearts were divided into 4 groups as follows: control group, PMNs were infused for 1 min on 1 min after reperfusion following global ischemia; IPC group, IPC was performed before global ischemia and PMNs were infused as the same manner; PPF group, Propofol (0.3µg/ml) was infused from perfusion until 5 min after reperfusion and PMNs were infused as the same manner; IPC/PPF group, IPC was performed before global ischemia and propofol was infused from perfusion until 5 min after reperfusion and PMNs were infused as the same manner. PMNs adhesion, heart rate, left ventricular developed pressure, dP/dt, coronary flow and creatinine kinase enzyme were measured.

RESULTS: Postischemic PMNs adhesion was reduced in IPC, propofol, and IPC/PPF group compared to the control group (30.8 ± 7.3%, 32.0 ± 3.9%, 20.9 ± 6.1% vs 75.7 ± 6.3%, P <0.05, respectively). There were no significant differences in PMNs postischemic adhesion between IPC group and PPF group, respectively and IPC/PPF group. There were no significant differences in changes in HR, LVDP, dP/dt, CF and CK among the four group.

CONCLUSIONS: These results suggest that IPC and propofol have no synergistic effect on reducing postischemic adhesion of PMNs.