This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pathology
[{'content': 'In myasthenia gravis, antibodies are present against:September 2012 \nSelect and explain. \nA. Muscarinic receptor proteins, B. Nicotinic receptor proteins, C. Protein actin, D. Protein myosin', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ans. B i.e. Nicotinic receptor proteinsMyasthenia gravisIt is an autoimmune neuromuscular disease leading to fluctuating muscle weakness and fatigability.It is an autoimmune disorder, in which weakness is caused by circulating antibodies that block acetylcholine receptors at the postsynaptic neuromuscular junction, inhibiting the excitatory effects of the neurotransmitter acetylcholine on nicotinic receptors throughout neuromuscular junctions.Myasthenia is treated medically with acetylcholinesterase inhibitors or immunosuppressants, and, in selected cases,thymectomy.', 'role': 'assistant'}]