Forearm P-31 nuclear magnetic resonance spectroscopy studies in oculopharyngeal muscular dystrophy.
Five siblings with autosomal dominant oculopharyngeal muscular dystrophy (OPMD) underwent P-31 Nuclear Magnetic Resonance Spectroscopy studies of forearm flexor muscles. Mean values of PCr/(PCr+Pi) in the patients were reduced (p = 0.01) and pH elevated (p = 0.02) in resting muscle when compared to controls. During exercise PCr/PCr+Pi) fell quickly to values less than controls (p less than 0.0001) despite submaximal exercise output and developed exercise-induced acidosis which exceeded that of controls (p = 0.05). Acidosis recovered slowly despite relatively normal recovery of PCr/(PCr+Pi) following exercise. Within the patient group, however, one member had normal resting, exercise and recovery values. The studies suggest that OPMD is a more widespread disorder of striated muscle than clinically appreciated. The pattern of findings observed in OPMD differs from those identified in denervation, disuse and mitochondrial myopathy.
Zochodne
D W
DW
Department of Medicine, Queen's University, Kingston, Ontario, Canada.
Koopman
W J
WJ
Witt
N J
NJ
Thompson
T
T
Driedger
A A
AA
Gravelle
D
D
Bolton
C F
CF
D000140:Acidosis, Lactic / Q000378:metabolism; D000368:Aged; D005080:Exercise Test; D005260:Female; D005542:Forearm / Q000502:physiology*; D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D008875:Middle Aged; D009136:Muscular Dystrophies / Q000378:metabolism*; D009801:Oculomotor Muscles / Q000378:metabolism*; D010609:Pharyngeal Muscles / Q000378:metabolism*; D010725:Phosphocreatine / Q000378:metabolism
D010725:Phosphocreatine