Oxypurine and Purine Nucleoside Concentrations in Renal Vein of Allograft Are Potential Markers of Energy Status of Renal Tissue

BackgroundImpairment of organ function derived from ischemia–reperfusion injury is an important problem in solid organ transplantation. Cell alterations induced by ischemia prime the tissue for subsequent damage that occurs during the reperfusion phase. Purine nucleosides and oxypurines are products of adenine nucleotides degradation. Reperfusion and reoxygenation are accompanied by production of reactive oxygen species and free radicals, which lead to damage of graft tissue. The aim of this study was to measure concentrations of adenine nucleotides and their metabolites in renal allograft vein as well as in recipient's peripheral veins during the reperfusion period and to evaluate their usefulness as markers of tissue metabolism in kidney allografts.MethodsThe study enrolled 20 renal transplant recipients. The first blood sample was taken from the recipient's ulnar vein before anastomosing of the kidney graft's vessels with recipient's iliac vessels. Samples were then taken from the renal allograft and ulnar veins 5 min after total graft reperfusion measured with an infrared camera. High-performance liquid chromatography (HPLC) was performed to measure whole blood and plasma concentrations of adenosine triphosphate (ATP), adenosine monophosphate (AMP), guanosine (Guo), inosine (Ino), hypoxanthine (Hyp), xanthine (Xan), uric acid (UA), and uridine (Urd).ResultsHyp and Xan concentrations were significantly increased in renal allograft vein after reperfusion as compared with peripheral vein during the pre- and post-reperfusion periods.ConclusionsThe results of the present study suggest that differences in Hyp and Xan concentrations between renal and peripheral veins reflect metabolic alterations in renal tissue during reperfusion and may be useful for graft function monitoring during reperfusion.