Acetylcholine Receptor Antibodies in Myasthenia Gravis

RECENT studies suggest the involvement of the acetylcholine receptor and the immune system in the pathogenesis of the neuromuscular disorder, myasthenia gravis.^{1 2 3 4 5}Patrick and Lindstrom¹produced an experimental myasthenic-like syndrome in rabbits by inoculation of acetylcholine receptors purified from electric eel. Using the high affinity cholinergic antagonist, alpha-bungarotoxin, Fambrough et al.²demonstrated an apparent reduction in the number of available acetylcholine receptors in muscle biopsies from myasthenic patients. Our own laboratory demonstrated the presence in myasthenic patients of a circulating globulin that blocked the binding of ¹²⁵I-labeled alpha-bungarotoxin to the acetylcholine receptor extracted from denervated rat skeletal muscle.³The globulin.