acetylcholinesterase(redirected from choline esterase I)
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Related to choline esterase I: cholinesterase test
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
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.
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).
Synonym(s): choline esterase I, "e"-type cholinesterase, specific cholinesterase, true cholinesterase
Farlex Partner Medical Dictionary © Farlex 2012
An enzyme in the blood and in certain tissues that catalyzes the hydrolysis of acetylcholine.
The American Heritage® Medical Dictionary Copyright © 2007, 2004 by Houghton Mifflin Company. Published by Houghton Mifflin Company. All rights reserved.
AcetylcholinesteraseA 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
Segen's Medical Dictionary. © 2012 Farlex, Inc. All rights reserved.
acetylcholinesteraseNeurophysiology 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
McGraw-Hill Concise Dictionary of Modern Medicine. © 2002 by The McGraw-Hill Companies, Inc.
One of a family of enzymes capable of catalyzing the hydrolysis of acetylcholine.
Medical Dictionary for the Health Professions and Nursing © Farlex 2012
acetylcholinesteraseAn ENZYME that rapidly inactivates ACETYLCHOLINE by breaking it down to acetic acid and choline. Also known as cholinesterase.
Collins Dictionary of Medicine © Robert M. Youngson 2004, 2005
acetylcholinesterasethe enzyme present in the synaptic cleft that destroys acetylcholine (see END PLATE).
Collins Dictionary of Biology, 3rd ed. © W. G. Hale, V. A. Saunders, J. P. Margham 2005
An enzyme that breaks down acetylcholine.
Mentioned in: Insecticide Poisoning
Gale Encyclopedia of Medicine. Copyright 2008 The Gale Group, Inc. All rights reserved.
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.
Millodot: Dictionary of Optometry and Visual Science, 7th edition. © 2009 Butterworth-Heinemann
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).
Medical Dictionary for the Dental Professions © Farlex 2012