Cholinesterases and termination of acetylcholine action
THE CONTEXT
Cholinesterases hydrolyze released acetylcholine. The source distinguishes acetylcholinesterase from butyrylcholinesterase by their location and function.
Fate of released acetylcholine
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Immediately after release, acetylcholine is hydrolyzed by cholinesterase, and choline is recycled.
Two enzyme types
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Acetylcholinesterase is the specific, or true, cholinesterase. It is strategically located at cholinergic sites and inactivates acetylcholine instantaneously.
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Butyrylcholinesterase is the nonspecific, or pseudo, cholinesterase. It is present in plasma and elsewhere and probably serves to metabolize ingested esters.