Which receptors are blocked in Myasthenia Gravis.

Ref. Guyton. 13th edition. Page.  96 Myasthenia gravis is an autoimmune disease characterized by autoantibodies against the acetylcholine (ACh) receptor of the neuromuscular junction, result- ing in muscular weakness predominantly affecting the facial muscles. Females are affected more frequently than males. Extra ocular muscle weakness may lead to ptosis and diplopia; the weakness worsens with repeated contractions. Respiratory muscle involvement may lead to death.
 There is an association with thymic hyperplasia and thymomas. Treatment is anticholinesterase agents, steroids, and thymectomy.