The action of acetylcholine at the neuromuscular junction is terminated primarily by:

The action of acetylcholine at the neuromuscular junction is terminated primarily by enzymatic breakdown by acetylcholinesterase. The acetylcholinesterase is attached to the basal lamina that fills the synaptic trough. There is no uptake of acetylcholine at the neuromuscular junction. A small amount of the acetylcholine will diffuse into the surrounding extracellular fluid but this is not the primary method by which its action is terminated.