Cause of myasthenia gravis
Myasthenia gravis is rare autoimmune disease caused by the formation of circulating antibodies to the nicotinic A-ch receptors. These antibodies destroy some of the receptors and bind others to neighboring receptors. The disease is characterized by rapid onset of fatigue with marked generalized weakness of muscles. The most commonly affected muscles are: extraocular muscles, facial, swallowing and mastication muscles.Ref: Textbook of physiology, Dir. Prof. AK Jain, 5th edition.
Decreased release of Ach at NM junction
Loss of muscles fibers
Destruction of receptors by antibody
Destruction of receptors by autolysis
Nervous system