The neuromuscular junction (NMJ) is the synapse between a motor neuron and a muscle fiber. Denervation leads to several changes at the NMJ:
1. Loss of Acetylcholine Receptors: The density of acetylcholine receptors on the muscle membrane decreases, impairing the muscle's ability to respond to neural stimuli. 2. Structural Alterations: The complex structure of the NMJ, which includes specialized folds in the muscle membrane, becomes simplified. 3. Reinnervation: In some cases, neighboring motor neurons may sprout new axons to reinnervate the denervated muscle fibers. This process can partially restore function, but often the reinnervated NMJs are not as efficient as the original ones.
