Acetylcholinesterase (AChE)
Definition
The enzyme that hydrolyses acetylcholine at cholinergic synapses. Inhibition by organophosphates or carbamates causes accumulation of acetylcholine at muscarinic, nicotinic and central receptors and produces the cholinergic toxidrome.
- Function
- Hydrolyses acetylcholine at cholinergic synapses
- Inhibited by
- Organophosphates, carbamates
- Inhibition effect
- Accumulated acetylcholine at receptors
- Resulting syndrome
- Cholinergic toxidrome
Common questions
What distinguishes the cholinergic toxidrome clinically?+
A combination of muscarinic signs such as salivation and bronchorrhea, nicotinic signs such as fasciculations and weakness, and central effects such as confusion and seizures appearing together.
Why does carbamate poisoning management differ from organophosphate poisoning?+
Carbamates bind AChE reversibly and typically resolve faster on their own, while organophosphates can bind essentially permanently unless treated promptly, making early antidote timing more critical for OPs.
How is AChE inhibition confirmed in a suspected poisoning case?+
Blood cholinesterase activity assays, using red cells or plasma, measure how far enzyme activity has dropped from a normal baseline, supporting the poisoning diagnosis.
Related terms
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- DUMBBELS
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