Article

Pre- and postsynaptic neuromuscular junction abnormalities in musk myasthenia

Department of Neurology, Leiden University Medical Center, K5Q-114, P.O. Box 9600, 2300 RC Leiden, The Netherlands.
Muscle & Nerve (Impact Factor: 2.31). 08/2010; DOI: 10.1002/mus.21642
Source: OAI

ABSTRACT Autoantibodies to muscle-specific kinase (MuSK) can cause myasthenia gravis (MG). The pathophysiological mechanism remains unknown. We report in vitro electrophysiological and histological studies of the neuromuscular junction in a MuSK MG patient. Low levels of presynaptic acetylcholine release and small miniature endplate potentials were found. This combination of pre- and postsynaptic abnormalities was supported by histology, revealing partially denervated postsynaptic areas, and some degeneration of postsynaptic folds. Results suggest that anti-MuSK antibodies reduce the stability of muscle-nerve contact.

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Erik H Niks