Purine metabolism during strenuous muscular exercise in man

Abstract

This study was designed to examine the influence of exercise on purine metabolism in man. In 15 men, the plasma uric acid concentration increased from 6.9 to 8.5 mg/dl following a 5000-m race and from 6.2 to 7.9 mg/dl in 11 men following a 42-km marathon. During a progressive exercise test on a cycle ergometer, the plasma uric acid concentration did not change significantly in 11 subjects. However, the plasma oxypurines increased from 19 μ M at rest to 50 μ M at exhaustion and the urinary excretion of oxypurines increased from 140 to 400 μmol/g creatinine. Intracellular ATP decreased from 5.17 to 2.91 μmol/g and ADP and AMP increased from 0.85 to 1.29 and from 0.12 to 0.15 μmol/g wet weight, respectively. These observations suggest that there is an accelerated degradation of purine nucleotides to the precursors of uric acid in skeletal muscle during vigorous exercise.