Pathophysiology of Myasthenia Gravis

Benjamin W. Hughes; Maria Luisa Moro De Casillas; Henry J. Kaminski

doi:10.1055/s-2004-829585

Seminars in Neurology, Table of Contents

Semin Neurol 2004; 24(1): 21-30
DOI: 10.1055/s-2004-829585

Pathophysiology of Myasthenia Gravis

Benjamin W. Hughes¹ , Maria Luisa Moro De Casillas¹ , Henry J. Kaminski¹ ^, ²

¹Department of Neurology, Case Western Reserve University, Louis Stokes Cleveland DVA Medical Center, University Hospitals of Cleveland, Cleveland, Ohio
²Department of Neurosciences, Case Western Reserve University, Louis Stokes Cleveland DVA Medical Center, University Hospitals of Cleveland, Cleveland, Ohio

Abstract

Myasthenia gravis (MG) is arguably the best understood autoimmune disease, and its study has also led to fundamental appreciation of mechanisms of neuromuscular transmission. MG is caused by antibodies against the acetylcholine receptor (AChR), which produce a compromise in the end-plate potential, reducing the safety factor for effective synaptic transmission. It is clear that AChR antibody destruction of the postsynaptic surface is dependent on complement activation. A muscle-specific kinase has been recently found to be an antigenic target in MG patients without antibodies against the AChR. Autoantibody production in MG is a T-cell-dependent process, but how a breakdown in tolerance occurs is not known. In MG there is an interesting differential involvement of muscle groups, in particular, the extraocular muscles. This article reviews normal neuromuscular transmission, mechanisms of the autoimmune process of MG, and differential susceptibility of eye muscles to MG.

KEYWORDS

Myasthenia gravis - neuromuscular transmission - acetylcholine receptor - neuromuscular junction

Full Text

References

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Henry J KaminskiM.D.

Department of Neurology, University Hospitals of Cleveland

11100 Euclid Avenue, Cleveland, OH 44106