acetylcholinesterase

(redirected from Cholinesterase enzyme)
Also found in: Dictionary, Thesaurus, Encyclopedia, Wikipedia.
Related to Cholinesterase enzyme: acetylcholinesterase, erythrocyte cholinesterase

acetylcholinesterase

 [as″ĕ-til-ko″lin-es´ter-ās]
an enzyme present in nervous tissue, muscle, and red blood cells that catalyzes the hydrolysis of acetylcholine to choline and acetic acid. This enzyme is present throughout the body, but is particularly important at the myoneural junction, where the nerve fibers terminate. Acetylcholine is released when a nerve impulse reaches a myoneural junction. It diffuses across the synaptic cleft and binds to cholinergic receptors on the muscle fibers, causing them to contract. cholinesterase splits acetylcholine into its components, thus stopping stimulation of the muscle fibers. The end products of the metabolism of acetylcholine are taken up by nerve fibers and resynthesized into acetylcholine. The drugs neostigmine, physostigmine, and pyridostigmine inhibit acetylcholinesterase and are used to treat myasthenia gravis, a disease in which the cholinergic receptors are attacked by autoantibodies. The drug extends the effect of acetylcholine on the muscle fiber. Called also true cholinesterase

a·ce·tyl·cho·lin·es·ter·ase

(a-sĕ'til-kō'lin-es'ter-ās), [MIM*100740]
The cholinesterase that hydrolyzes acetylcholine to acetate and choline within the central nervous system and at peripheral neuroeffector junctions (for example, motor endplates and autonomic ganglia).

acetylcholinesterase

(ə-sēt′l-kō′lə-nĕs′tə-rās′, -rāz′)
n.
An enzyme in the blood and in certain tissues that catalyzes the hydrolysis of acetylcholine.

Acetylcholinesterase

A hydrolase in the membrane of postsynaptic cells which metabolises acetylcholine into choline and acetic acid in the synaptic cleft, restoring it to a ground state, in preparation for the next nerve impulse.
Location CNS, red cells, motor endplates

acetylcholinesterase

Neurophysiology A hydrolase that metabolizes acetylcholine to acetyl and choline in the synaptic cleft, restoring it to a ground state, in preparation for the next nerve impule; acetylcholinesterase is found in the CNS, RBCs, motor endplates

a·ce·tyl·cho·lin·es·ter·ase

(AChE) (as'ĕ-til-kō'lin-es'tĕr-ās)
One of a family of enzymes capable of catalyzing the hydrolysis of acetylcholine.

acetylcholinesterase

An ENZYME that rapidly inactivates ACETYLCHOLINE by breaking it down to acetic acid and choline. Also known as cholinesterase.

acetylcholinesterase

the enzyme present in the synaptic cleft that destroys acetylcholine (see END PLATE).

Acetylcholinesterase

An enzyme that breaks down acetylcholine.
Mentioned in: Insecticide Poisoning

acetylcholinesterase 

An enzyme that degrades and inactivates acetylcholine. This compound is mainly found in neurons and at neuromuscular junctions. Drugs that inhibit this enzyme (e.g. diisopropyl fluorophosphate, physostigmine, edrophonium, echothiophate, DFP) can be used in the diagnosis and possible treatment of myasthenia gravis as well as certain forms of esotropia and glaucoma. Syn. specific cholinesterase. See anticholinesterase drugs.

a·ce·tyl·cho·lin·es·ter·ase

(as'ĕ-til-kō'lin-es'tĕr-ās) [MIM*100740]
Cholinesterase that hydrolyzes acetylcholine to acetate and choline within the central nervous system and at peripheral neuroeffector junctions (e.g., motor endplates and autonomic ganglia).
References in periodicals archive ?
As Cholinesterase enzyme is produced in the liver its assay can be of importance.
The symptoms of pesticide poisoning are a result of the binding and inhibition of cholinesterase enzymes at the synapse (Hernandez et al., 2004), resulting in the accumulation of the neurotransmitter acetylcholine and subsequent over-stimulation of cholinergic systems such as muscles, glands and nerves.
Akhtar, Detrmination of Toxicity of Clerodendrum inerme and cypermethrin against Tribolium castaneum and their effects on acid phosphatase and cholinesterase enzymes, Proc.
Pralidoxime is used to reactivate cholinesterase enzymes, but is ineffective once the enzyme has become irreversibly bound to organophosphate.
Normally, choline is hydrolyzed by the catalytic action of cholinesterase enzymes. Higher concentrations of the enzyme lead to lower amounts of choline in the synaptic gap.
Plasma cholinesterase is substantially more sensitive to anticholinergic agents than red cell cholinesterase, whereas the latter more closely reflects the activity of cholinesterase enzymes within the nervous system.