Direct observation of the phosphate acceptor and phosphagen pool sizes in vivo

Van Waarde, A., van den Thillart, G., Verhagen, M., Erkelens, C., Addink, A. & Lugtenburg, J., May-1990, In : American Journal of Physiology. 258, 5 Pt 2, p. R1132-1139

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Earthworms were subjected to environmental anoxia (200 min) and electrical stimulation (5 min, 6 V, 50 Hz). The levels of high-energy phosphate compounds and the intracellular pH were monitored during anoxia, muscular contraction, and recovery by in vivo phosphorus-31 nuclear magnetic resonance (31P-NMR). Several key metabolites were determined by enzymatic analysis and reversed-phase high-performance liquid chromatography of perchlorate extracts. Because lombricine, the phosphagen phosphate acceptor of earthworms, is a phosphodiester, 31P-NMR permitted direct analysis of the extent of phosphorylation of the lombricine pool in vivo. Total lombricine, lombricine phosphate, ATP, and H+ were measured by NMR, and free ADP was calculated from the lombricine kinase equilibrium constant. The ADP concentration was not significantly changed by anoxia, but it rose threefold after stimulation. L-Lactate accumulated on stimulation, whereas multiple end products (L-lactate, alanine, succinate, and glutamine) were formed during environmental anaerobiosis.

Original languageEnglish
Pages (from-to)R1132-1139
JournalAmerican Journal of Physiology
Issue number5 Pt 2
Publication statusPublished - May-1990


  • Adenosine Diphosphate, Animals, Anoxia, Electric Stimulation, Energy Metabolism, Magnetic Resonance Spectroscopy, Oligochaeta, Phosphates, Phosphorylation, Serine

ID: 15891755