Pathophysiology of myasthenia gravis and Lambert-Eaton syndrome.

The first part of this article delineates the most important structural and functional bases of neuromuscular transmission under normal conditions. Next, the main effects of myasthenic antibodies at the neuromuscular junction are described. The article emphasizes the role of inflammation as a transient phase proceeding the degenerative changes of the neuromuscular junction observed in myasthenia gravis. The article ends with a discussion of the principal molecular and physiologic changes accounting for the impairment of neuromuscular transmission in Lambert-Eaton Myasthenic Syndrome.