Congenital myopathies: disorders of excitation–contraction coupling and muscle contraction

Excitation-Contraction Coupling Alterations in Myopathies

During the complex series of events leading to muscle contraction, the initial electric signal coming from motor neurons is transformed into an increase in calcium concentration that triggers sliding of myofibrils. This process, referred to as excitation-contraction coupling, is reliant upon the calcium-release complex, which is restricted spatially to a sub-compartment of muscle cells ("the tr...

Congenital myopathies.

This review focuses on congenital myopathies, a distinct but markedly heterogeneous group of muscle disorders that present with muscle weakness and typically appear at birth or in infancy. These myopathies have characteristic histopathologic abnormalities on muscle biopsy, allowing a preliminary morphologic classification. Advances in molecular genetics have allowed a more rational classificati...

I-13 Muscle ryanodine receptor in congenital myopathies and channelopathies

potentials and twitch force were measured in muscle strips obtained from patients and controls. Of the 36 patients, 25 presented with chronic muscle weakness of varying degrees, up to wheelchair-dependence. The weakness was associated with intracellular Na overload and edema. Older patients revealed a vacuolar myopathy or a progressive muscular dystrophy. Weakness, intracellular Na overload and...

Congenital myopathies and congenital muscular dystrophies.

Congenital myopathies and congenital myopathic dystrophies are distinct groups of inherited diseases of muscle, genetically heterogeneous, that manifest in early life or infancy. Congenital myopathic dystrophy is characterized by a dystrophic pattern, whereas no necrotic or degenerative changes are present in congenital myopathies. Much progress has been made in recent years in clarifying the c...

Excitation-contraction coupling in skeletal muscle.