Urate uptake and lowered atp levels in human muscle after high intensity intermittent exercise. Hellsten, Y., B. Sj[diaeresis]odin, E. A. Richter, and J. Bangsbo. Copenhagen Muscle Research Centre, August Krogh Institute, Copenhagen, Denmark, National Defense Research Establishment, and Department of Physiology and Pharmacology, Karolinska Institute, Stockholm, Sweden.
APStracts 4:0274E, 1997.
The exchange of purines in exercised and rested muscle and their relation to muscle ATP levels following intense intermittent exercise was investigated. Seven subjects performed one-legged knee extensor exercise on two occasions; without (Control; C) and with (High purines; HP) additional arm-exercise. There was a greater net release of hypoxanthine by the exercised muscle during the recovery period in HP compared to C (185+/-44 [Mean+/-SE] vs. 101+/-30 [mu]mol/kg muscle; P<0.05). During recovery the arterial urate concentration was higher in HP compared to C (peak: 585+/-48 vs. 355+/-20 [mu]mol/l; P<0.05). The exercised but not the rested muscle extracted a marked amount of urate (330 [mu]mol/kg muscle) from plasma in the HP trial. Muscle ATP levels after 90 min of recovery in HP were lower than at rest (24.3+/-0.6 vs. 20.1+/-1.1 mmol/kg d.w.). The present data suggests that a single session of long-term high intensity intermittent exercise causes a significant release of purines from the muscle into blood which contributes to a sustained lowered level of the muscle ATP concentration. Furthermore, intensely exercised muscle extracts urate when plasma urate is elevated, an event which may be of importance for the replenishment of oxidized muscle urate stores.

Received 7 October 1997; accepted in final form 9 December 1997.
APS Manuscript Number E478-7.
Article publication pending Am. J. Physiol. (Endocrinol. Metab.).
ISSN 1080-4757 Copyright 1997 The American Physiological Society.
Published in APStracts on 7 January 1998