ATP breakdown products in human skeletal muscle during prolonged exercise to exhaustion

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Bibliographische Detailangaben
Deutscher übersetzter Titel:Produkte des ATP-Abbaus im menschlichen Skelettmuskel waehrend erschoepfender koerperlicher Belastung
Autor:Norman, B.; Sollevi, A.; Kaijser, L.; Jansson, E.
Erschienen in:Clinical physiology
Veröffentlicht:7 (1987), S. 503-509, Lit.
Format: Literatur (SPOLIT)
Publikationstyp: Zeitschriftenartikel
Medienart: Gedruckte Ressource
Sprache:Englisch
ISSN:0144-5979, 1365-2281
Schlagworte:
ATP
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Erfassungsnummer:PU199311067625
Quelle:BISp

Abstract

To study changes in muscle energy state during prolonged exercise, especially in relation to fatigue, muscle biopsies were obtained from seven healthy males working until exhaustion on a cycle ergometer at 68 (63-74) of their maximal oxygen uptake. Biopsies were taken at rest, after 15 and 45 min of exercise and at exhaustion, and analysed for ATP, ADP, AMP, inosine monophosphate (IMP) and hypoxanthine content by high performance liquid chromatography (HPLC), and for creatine phosphate (CP), lactate and glycogen by enzymatic fluorometric techniques. Glycogen content at exhaustion was approximately 30 of the pre-exercise level. The CP content decreased steeply during the first 15 min of exercise (P < 0.01) and continued to decrease during the rest of the exercise period (P < 0.05). Pronounced increases in contents of IMP (64 P < 0.001) and hypoxanthine (69, P < 0.05) were found when exhaustion was approaching. Furthermore, energy charge (EC; (ATLP + 0.5 ADLP)/(ATP + ADP + AMP)) was decreased at exhaustion (P < 0.05). The increases in IMP and hypoxanthine which occurred when exhaustion was approaching during prolonged submaximal exercise together with the decrease in EC during this phase of exercise suggest a failure of the exercising skeletal muscle to regenerate ATP at exhaustion. Verf.-Referat