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Updated: Aug 19, 2026

Levator Auris Longus Preparation for Examination of Mammalian Neuromuscular Transmission Under Voltage Clamp Conditions
Published on: May 5, 2018
Sodium channel defects in myotonia and periodic paralysis
1Department of Neurobiology, Harvard Medical School, Massachusetts General Hospital, Boston, Massachusetts 02114, USA.
Abstract:
Myotonias and periodic paralyses constitute a diverse group of inherited disorders of muscle in which the primary defect is an alteration in the electrical excitability of the muscle fiber. The ion channel defects underlying these excitability derangements have recently been elucidated at the molecular and functional levels. This review focuses on sodium channel mutations that disrupt inactivation and thereby cause both the enhanced excitability of myotonia (muscle stiffness due to repetitive discharges) and the inexcitability resulting from depolarization during attacks of paralysis.
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