Mitochondrial dysfunction of human muscle in chronic alcoholism detected by using 31P-magnetic resonance spectroscopy and near-infrared light absorption.
We previously examined the effect of alcohol on muscle energy metabolism in chronic alcoholics by using 31P-magnetic resonance spectroscopy. Measurements of intracellular pH and PCr index [PCr/(PCr + Pi)] during resting, hand grasping, and recovery in the left flexor digitorum superficialis muscle of alcoholics with neurological signs showed a marked decrease and delayed recovery of pH, but rapid recovery of PCr index indicating that the muscle produces lactate during and after exercise to maintain the ATP level. To clarify the reason for this preference for anaerobic metabolism, we conducted simultaneous measurements of the muscle blood supply during and after exercise by using the near-infrared light method and energy metabolism by using 31P-magnetic resonance spectroscopy. In alcoholics with neurological signs, we observed a significant increase of oxyhemoglobin after exercise with a slight increase of total hemoglobin. In healthy volunteers and chronic alcoholics without neurological signs, such an overshoot of oxyhemoglobin was not observed. We conclude that chronic alcoholics with neurological signs have an abnormality of aerobic metabolism owing to muscle mitochondrial dysfunction.
Haida
M
M
Department of Neurology, Tokai University School of Medicine, Kanagawa, Japan.
Yazaki
K
K
Kurita
D
D
Shinohara
Y
Y
D000136:Acid-Base Equilibrium / Q000502:physiology; D000328:Adult; D000437:Alcoholism / Q000503:physiopathology*; D004734:Energy Metabolism / Q000502:physiology*; D015444:Exercise / Q000502:physiology; D006801:Humans; D006863:Hydrogen-Ion Concentration; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D008875:Middle Aged; D008931:Mitochondria, Muscle / Q000502:physiology*; D018482:Muscle, Skeletal / Q000294:innervation; D009460:Neurologic Examination; D010108:Oxyhemoglobins / Q000378:metabolism; D010523:Peripheral Nervous System Diseases / Q000503:physiopathology; D010725:Phosphocreatine / Q000378:metabolism; D012016:Reference Values; D019265:Spectroscopy, Near-Infrared
D010108:Oxyhemoglobins; D010725:Phosphocreatine