Hereditary muscle channelopathies

作者：Lehmann Horn F; Jurkat Rott K^*

来源：Nervenheilkunde, 2011, 30(10): 765-+.

• Ion channels
• muscle disorders
• muscle stiffness
• muscle weakness
• muscle degeneration
• myotonia
• periodic paralysis
• malignant hyperthermia
• core myopathy

A combination of electrophysiological and molecular genetic studies has resulted in the discovery of certain skeletal muscle disorders to be caused by pathologically functioning ion channels. The group of thus defined hereditary "muscle channelopathies" comprises non-dystrophic myotonias, dyskalemic periodic paralyses, central-core myopathy and multi-minicore myopathy, as well as malignant hyperthermia. They have in common an impaired muscle excitation or excitation-contraction coupling that is caused by ion channel mutations. Most muscle channelopathies are considered benign diseases. However, muscle hypermetabolism resulting in muscle stiffness and hyperthermia as in an event of malignant hyperthermia can be life-threatening. Also, forms of familial periodic paralysis can be severe when they produce serious dyskalemia that disturbs cardiac excitation conduction. The hypokalemia is most pronounced in thyrotoxic periodic paralysis. Some of the periodic paralyses are associated with a progressive permanent weakness. The weakness is explained by strongly depolarized, inexcitable muscle fibers that accumulate sodium and water. Drugs that repolarize the fiber membrane can restore muscle strength and may prevent progression. Expression studies of putative mutations have become standard in supporting the disease-causing nature of mutations.

• 出版日期2011