In Myasthenia gravis, the fundamental defect at the neuromuscular junction is:
Correct Answer: Failure of ACh to attach to the postsynaptic receptor
Description: Myasthenia gravis is the principal disease affecting the neuromuscular junction. In this process, the fundamental defect is not a deficiency of ACh or its release, but rather a failure of ACh to attach to the postsynaptic receptor, as a result of blockade by an antibody at the receptor site or of destruction of the membrane by antibody attack. There are several quite different synaptic disorders caused by botulism, aminoglycoside antibiotics, and the antibodies of the Lambe-Eaton myasthenic syndrome, which impede presynaptic release of ACh. Ref: Ropper A.H., Samuels M.A. (2009). Chapter 45. Electrophysiologic and Laboratory Aids in the Diagnosis of Neuromuscular Disease. In A.H. Ropper, M.A. Samuels (Eds), Adams and Victor's Principles of Neurology, 9e.
Category:
Physiology
Get More
Subject Mock Tests
Practice with over 200,000 questions from various medical subjects and improve your knowledge.
Attempt a mock test nowMock Exam
Take an exam with 100 random questions selected from all subjects to test your knowledge.
Coming SoonGet More
Subject Mock Tests
Try practicing mock tests with over 200,000 questions from various medical subjects.
Attempt a mock test now