Uricemia in juvenile pigs model: effect of nephrectomy and potassium oxonate

Uric acid is the end product of dietary and endogenous purine metabolism in humans and higher primates. In all lower mammalian species it is converted to allantoin by liver uricase. The aim of this study was to investigate the uric acid turnover in pig model after nephrectomy surgery, fructose-enriched diet and potassium oxonate application. The first experiment was performed using 4 intact control pigs and 8 nephrectomized (5/6 nephrectomy) pigs. Both groups were fed high-fat diet enriched with 20% of fructose for 3 weeks. During the second experiment, as another approach to induce hyperuricemia, potassium oxonate solution (POx) was administered intravenously to 4 healthy pigs, once or twice per day. In the third preliminary experiment one healthy and two nephrectomized (9/10 nephrectomy) pigs were infused with POx to induce hyperuricemia. Results showed that 5/6 nephrecotomy did not affect plasma uric acid concentration for 25 days following surgery. The consumption of the high-fat diet enriched with 20% of fructose did not result in the rise of plasma uric acid, either in healthy or nephrectomized pigs. Administration of POx solution to healthy and 9/10 nephrectomized pigs resulted in significantly increased plasma uric acid concentrations for 18 h and 24 h, respectively, following a single POx infusion. The present study expands today available data on uric acid metabolism in pigs as a model for exploring uricemia in human with kidney dysfunction.