Cholinesterase enzyme family

The cholinesterase enzyme family consists primarily of two related enzymes: acetylcholinesterase and butyrylcholinesterase. Both catalyze the hydrolysis of the neurotransmitter acetylcholine into choline and acetic acid—a reaction essential for terminating neurotransmission at cholinergic synapses. Acetylcholinesterases are found mainly at neuromuscular junctions and neural synapses where they rapidly degrade acetylcholine after its release. Butyrylcholinesterases are present mainly in plasma and liver with broader substrate specificity. These enzymes play critical roles in nervous system function as well as detoxification processes. They are major therapeutic targets for drugs treating neurodegenerative diseases such as Alzheimer’s disease—and also key targets/inhibitors involved in pesticide/nerve agent toxicity.

Other names

CholinesterasesAcetylcholine esterase familyAChE and BChE enzymesTrue cholinesterase (for acetylcholinesterase)Pseudocholinesterase (for butyrylcholinesterase)RBC cholinesterase (acetylcholinesterase)Plasma cholinesterase (butyrylcholinesterase)

Drugs targeting this enzyme act primarily as enzyme inhibitors—either reversible or irreversible—leading to increased levels of acetylcholine at synapses. This can enhance cholinergic transmission in diseases like Alzheimer’s or cause toxicity in the case of poisoning.