31P-magnetic resonance spectroscopy assessment of subnormal oxidative metabolism in skeletal muscle of renal failure patients

• Published in: The Journal of clinical investigation Vol. 91; no. 2; pp. 420 - 424
• Main Authors: MOORE, G. E, BERTOCCI, L. A, PAINTER, P. L
• Format: Journal Article
• Language: English
• Published: Ann Arbor, MI American Society for Clinical Investigation 01.02.1993
• Subjects: Adenosine Triphosphate - metabolism; Adult; Biological and medical sciences; Energy Metabolism; Erythropoietin - therapeutic use; Female; Humans; Kidney Failure, Chronic - metabolism; Kidney Transplantation; Magnetic Resonance Spectroscopy; Male; Medical sciences; Middle Aged; Muscles - metabolism; Nephrology. Urinary tract diseases; Nephropathies. Renovascular diseases. Renal failure; Oxygen Consumption; Renal Dialysis; Renal failure; Physical exercise; Human; Urinary system disease; Hemodialysis; Renal failure; Exploration; NMR spectrometry; Homotransplantation; Striated muscle; Metabolism; Kidney
• ISSN: 0021-9738; 1558-8238
• DOI: 10.1172/jci116217

In hemodialysis patients, erythropoietin increases hemoglobin, but often the corresponding increase in peak oxygen uptake is low. The disproportionality may be caused by impaired energy metabolism. 31P-magnetic resonance spectroscopy was used to study muscle energy metabolism in 11 hemodialysis patients, 11 renal transplant recipients, and 9 controls. Measurements were obtained during rest, static hand-grip, and rhythmic hand-grip; recoveries were followed to baseline. During static hand-grip, there were no between-group differences in phosphocreatine (PCr), inorganic phosphate (Pi), or PCr/(PCr + Pi), although intracellular pH was higher in hemodialysis patients than transplant recipients. During rhythmic hand-grip, hemodialysis patients exhibited greater fatigue than transplant recipients or controls, and more reduction in PCr/(PCr + Pi) than transplant recipients. Intracellular pH was higher in controls than either hemodialysis patients or transplant recipients. Recoveries from both exercises were similar in all groups, indicating that subnormal oxidative metabolism was not caused by inability to make ATP. The rhythmic data suggest transplantation normalizes PCr/(PCr + Pi), but not pH. In hemodialysis patients, subnormal oxidative metabolism is apparently caused by limited exchange of metabolites between blood and muscle, rather than intrinsic oxidative defects in skeletal muscle.