Cholinesterase inhibitor

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Acetylcholinesterase

A cholinesterase inhibitor or anticholinesterase is a chemical that inhibits a cholinesterase enzyme from breaking down acetylcholine, so increasing both the level and duration of action of the neurotransmitter acetylcholine.

Contents

1 Uses
2 Examples

2.1 reversible inhibitor
2.2 quasi-irreversible inhibitor

3 Effects
4 See also

Uses

Anticholinesterases occur naturally as venoms and poisons, are used as weapons in the form of nerve agents, and are used medicinally to treat diseases such as myasthenia gravis and Alzheimer's disease, and as an antidote to anticholinergic poisoning. In myasthenia gravis, they are used to increase neuromuscular transmission.

Examples

reversible inhibitor

Compounds which function as reversible competitive or noncompetitive inhibitors of cholinesterase are those most likely to have therapeutic uses. These include:

Organophosphates
*metrifonate
Carbamates
*physostigmine
*neostigmine
*pyridostigmine
*ambenonium
*demarcarium
*rivastigmine
Phenanthrine derivatives
*galantamine
Piperidines
*donepezil, also known as E2020
Tacrine, also known as tetrahydroaminoacridine (THA')
Edrophonium

quasi-irreversible inhibitor

Compounds which function as quasi-irreversible inhibitors of cholinesterase are those most likely to have use as chemical weapons or pesticides. These include:

Organophosphates
*echothiophate
*isoflurophate
*diisopropyl fluorophosphate
*cyclosarin
*sarin
*soman
*tabun
*VX
*VE
*VG
*VM
*diazinon
*malathion
*parathion
Carbamates
*aldicarb
*bendiocarb
*bufencarb
*carbaryl
*carbendazim
*carbetamide
*carbofuran
*chlorbufam
*chloropropham
*ethiofencarb
*formetanate
*methiocarb
*methomyl
*oxamyl
*phenmedipham
*pinmicarb
*pirimicarb
*propamocarb
*propham
*propoxur

Effects

Some major effects of anticholinesterase:

Actions on the autonomic nervous system, that is parasympathetic nervous system will cause bradycardia, hypotension, hypersecretion, bronchoconstriction, GIT hypermotility, and decrease intraocular pressure.