Neurology · 1977 · 37 citations · 0 references
MedicineAnatomyPhysiologyBiomechanicsCalcium HomeostasisMechanobiologyMuscle MechanicsMuscle PhysiologyMuscle StrengthMuscle StructureMuscle TissueMuscular StrengthContractile ProteinsMuscle Contractile FunctionMuscle Fiber CharacteristicsMuscle Fiber DiameterMuscle Ultrastructure ChangesSkeletal Muscle Fiber TypesSkeletal Muscle PhysiologyUltrastructural Alterations
Despite focal degeneration and simplification of the postsynaptic region in Duchenne dystrophy, the postsynaptic acetylcholine receptor (AChR) is preserved. This is in contrast to myasthenia gravis where similar postsynaptic alterations are invariably associated with a marked decrease in AChR. There is no extrajunctional spread of AChR in Duchenne dystrophy. The amplitude and frequency of miniature end-plate potentials and the number of transmitter quanta released by nerve impulse are normal but the resting membrane potential is lower than normal. The findings indicate that the release and the postsynaptic responsiveness to acetylcholine are intact in Duchenne dystrophy.