Abstract
We have used 31P nuclear magnetic resonance spectroscopy to study noninvasively the metabolic state of skeletal muscle in vivo in diabetic patients under poor and good control. The concentrations of phosphocreatine (PCr), inorganic phosphate (Pi) and ATP in hamstring muscles were measured during rest, aerobic exercise and recovery from exercise. Under poor control, diabetic patients (with both IDDM and NIDDM) show evidence of a reduced muscle energy state with the following abnormalities compared with a normal subject. First, PCr concentrations are lower than normal and continue to decline during exercise. Second, Pi concentrations are higher than normal during exercise. Third, PCr resynthesis in post exercise recovery is abnormally prolonged. Under good control, these abnormalities are improved to almost near normal.
These findings demonstrate the impaired energy metabolism which is due to inhibited glycolysis and/or mitochondrial oxidative activity in skeletal muscles of diabetic patients under poor control. 31P nuclear magnetic resonance spectroscopy may have potential clinical application in defining the biochemical basis of energy metabolism in diabetic patients.
