AN ISOCRATIC, REVERSED-PHASE HPLC METHOD FOR THE DETERMINATION OF POSTISCHEMIC EFFLUX OF PURINES AND PYRIMIDINES DURING REPERFUSION OF ISOLATED LIVER

An isocratic, reversed-phase HPLC method was developed for the determi nation of the rates of purine and pyrimidine efflux during early reper fusion of isolated organs after non-perfusion cold conservation. The m ethod enables determination of uric acid, cytidine, xanthine, hypoxant hine, uridine, AMP, inosine, and adenosine in liver perfusate using a standard C-18 column (25 cm length). Peaks are resolved by elution wit h buffer containing 1% acetonitrile, 20 mM potassium citrate (pH 6.25) , and 25-55 mM tetramethylammonium. The effects of pH and solvents on peak retention times are described. As an example of the application o f the method, the effects of allopurinol on the rates of postischemic efflux of purines and pyrimidines during reperfusion of liver stored i n the cold for 24 h in Euro-Collins solution were studied.