The role of oxygen free radicals in organ preservation.

There is controversy over the role of oxygen free radical-induced damage in preserved organs following reperfusion. Furthermore, there has been no definitive study that shows a dramatic improvement in organ functions, delayed graft functions, or improved longevity in organ transplants with oxygen free radical scavenger therapy. However, the presence of glutathione in a new organ preservation solution (University of Wisconsin, UW, solution) yields improved preservation of the liver and heart. The beneficial effect of glutathione may involve in scavenging of cytotoxic products of oxygen metabolism. The results discussed here show that glutathione improves liver preservation. Also, it is shown that glycine, and amino acid component of glutathione, can also give cytoprotection to the rabbit and dog liver tested by either isolated perfusion or orthotopic transplantation. Thus, there may be an involvement of oxygen free radicals in damage to organs hypothermically preserved and transplanted. The injury may occur within the cells or may be due to oxygen within the cells or may be due to oxygen free radicals generated in the extracellular environment.