Supplementation of Nucleoside-Nucleotide Mixture Enhances Functional Recovery and Energy Metabolism Following Long-Time Hypothermic Heart Preservation

OG-VI, a well-balanced mixture of nucleoside and nucleotides, has been demonstrated to have a favorable effect on energy metabolism. In this study, we tested the hypothesis that addition of OG-VI to the University of Wisconsin solution can improve the cardiac functional recovery following long-time hypothermic preservation. Forty-two male Wistar rats were randomized into four groups. After 30-min of isolated working heart perfusion, the rat hearts were arrested with St. Thomas cardioplegic solution and preserved at 4°C in saline, OG-VI, UW, and UW+OG-VI, respectively. After 12-h of preservation, the hearts were reperfused for 60-min during which the recovery of cardiac functions were monitored continuously. Myocardial adenine nucleotides were analyzed using high-performance liquid chromomatograph. In the UW+OG-VI group, the recovery of cardiac output, coronary flow, aortic flow, rate-pressure product, left ventricle stroke volume, and stroke work were significantly higher than other groups ( P < 0.05). Furthermore, all phosphate high-energy compounds were significantly higher in the UW+OG-VI group than in the other groups ( P < 0.05). Coronary vascular resistance and myocardial wet/dry weight ratio were obviously lower in the UW+OG-VI group, compared to the other groups ( P < 0.05). Heart function was better recovered when nucleoside-nucleotide mixture was added to UW solution during long-time hypothermic rat heart preservation. The mechanism is not totally clear, but enhancement of high-energy phosphate production is possible.