Disorders affecting the acetylcholine receptor: myasthenia gravis and congenital myasthenia.

Myasthenia gravis (MG) is an autoimmune disease in which anti-acetylcholine receptor antibodies (anti-AChR) cause loss of functional endplate AChR by increasing AChR degradation, and by complement-mediated destruction. MG anti-AChR binds to regions on the human AChR which can be defined by monoclonal antibodies (mabs). Several congenital forms of myasthenia have been described, three of which may directly involve abnormalities of the AChR, including one in which the open-time of the ion channel is prolonged.