EFFECT OF MUSCULAR EXERCISE ON THE CONCENTRATION OF URIDINE AND PURINE-BASES IN PLASMA - ADENOSINE-TRIPHOSPHATE CONSUMPTION-INDUCED PYRIMIDINE DEGRADATION

To identify whether muscular exercise increases the plasma concentrati on of uridine and of purine bases, the effect of rigorous muscular exe rcise was determined in five healthy men with a bicycle ergometer. Twe nty-five-minute muscular exercise at 65% maximum O-2 consumption incre ased the concentration of uridine, purine bases, and inorganic phospha te in plasma and of NH3 and lactic acid in blood, These results sugges t that exercise-induced excessive adenosine triphosphate (ATP) consump tion enhanced not only purine degradation but also pyrimidine degradat ion (uridine triphosphate [UTP] --> uridine diphosphate [UDP] --> urid ine monophosphate [UMP] --> uridine) in exercising muscles. Copyright (C) 1997 by W.B. Saunders Company.