[Reperfusion injury after heart-lung transplantation--OP41483-alpha-CD (prostaglandin I2 analogue) as a preventive for the reperfusion injury, especially the oxygen derived free radicals].
In clinical heart-lung transplantation, reperfusion injury is a serious problem. This study was undertaken to evaluate the preventive effect of OP 41483-alpha-CD (OP) as a stable prostaglandin I2 analogue on the reperfusion injury, especially oxygen derived free radicals after the heart-lung transplantation. The heart-lung transplantation was performed according to the Schäefers' method. Explanted heart-lung block was immersed and preserved in the UW solution for just 4 hours at 4 degrees C. In the OP group, OP was administered to the grafts through the pulmonary artery for 25 minutes before and after the reperfusion. No spin adducts were detected in the plasma before harvest of the graft by ESR spectroscopy. But after the onset of reperfusion, free radical in the plasma could be detected. Those signals were 2.007 of the g factor and 15.5 G of the hyperfine splitting constancy (aN). These findings suggested that the free radical detected in the blood of this model was hydroxyl radical. Max dp/dt, left ventricular pressure and cardiac index were higher in the OP group than in the control group after reperfusion, but there was no difference in the left ventricular end-diastolic pressure between two groups. And adenosine triphosphate contents of the myocardial cell was higher in the OP group than in the control group at 60 min after the onset of reperfusion. Oxygenation by the graft's lung was better in the OP group than in the control group after reperfusion. Radical intensities of the plasma by ESR after reperfusion were significantly higher in the pulmonary vein than in the coronary sinus. When OP was administered, radical intensities in the lung and the plasma of the pulmonary vein were significantly lower in the OP group than in the control group. Thiobarbituric acid-reactive substances increased gradually, in two groups with less increase in the OP group. These show that the free radicals, especially.OH generated from the transplanted heart and lung contribute to the reperfusion injury. The platelet counts in the systemic blood, furthermore, did not change appreciably in the OP group, but decreased rapidly in the control group. Probably the microemboli formation was partially inhibited by the administration of OP. Following the onset reperfusion, the free radicals attack the cell membranes and cause the cell damage. When OP was administered through the pulmonary artery, less free radicals were generated in the lung, and the microemboli were possibly inhibited by platelets anti-agglutination. OP administration is useful in the heart-lung transplantation.
Takeuchi
K
K
First Department of Surgery, Hirosaki University School of Medicine, Aomori, Japan.
D000818:Animals; D004285:Dogs; D011464:Epoprostenol / Q000031:analogs & derivatives* / Q000627:therapeutic use; D005609:Free Radicals; D016041:Heart-Lung Transplantation; D015428:Myocardial Reperfusion Injury / Q000378:metabolism / Q000517:prevention & control*; D010100:Oxygen / Q000378:metabolism*; D010975:Platelet Aggregation Inhibitors / Q000627:therapeutic use*
D005609:Free Radicals; D010975:Platelet Aggregation Inhibitors; D011464:Epoprostenol; C035847:ataprost; D010100:Oxygen