Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: EC:3.1.1.8 (cholinesterase)
12,691 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The interaction of three new non-depolarizing neuromuscular blocking agents--atracurium, vecuronium and Duador--on human red cell acetylcholinesterase (AChE; EC 3.1.1.7) and human plasma butyrylcholinesterase (BuChE; EC 3.1.1.8) was investigated. The binding of these neuromuscular blockers to human plasma proteins (protein binding) was also studied with a new method not requiring dialysis. For sake of comparison the protein binding and the interaction of tubocurarine and pancuronium with AChE and BuChE were observed also. None of the drugs studied was a substrate of AChE or BuChE. All had a relatively weak inhibitory effect on AChE (I50 greater than 10(-5) mol litre-1 in assay systems containing 5% haemolysed red cells). Of the three new neuromuscular blockers, vecuronium and Duador were relatively potent inhibitors of BuChE (I50 less than 10(-5) mol litre-1 in assay systems containing 5% plasma), but less potent than pancuronium (I50 = 6.1 X 10(-8) mol litre-1). All neuromuscular blocking drugs tested, especially vecuronium and pancuronium, were strongly (77-91%) bound to plasma proteins.
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PMID:Protein binding of atracurium and other short-acting neuromuscular blocking agents and their interaction with human cholinesterases. 613 40

Elevated Alpha-Fetoprotein (AFP) values in the amniotic fluid are most frequently associated with neural occlusive disturbances or, in rare cases, with other external malformations of the foetus. In this article, the authors report on two cases where the elevated AFP had not been due to fetal malformations. In the first case, the cause was identified as foetal proteinuria, probably in the sense of an autosomal-recessive hereditary congenital nephrosis, whereas in the second case the phenomenon was possibly due to a "foetal distress" syndrome. Attention is drawn to the importance of elevated AFP levels. The possibilities of further prenatal differential diagnosis are discussed, such as ultrasound, determination of acetyl cholinesterase AChE) activity and assessment of the amniotic fluid cells.
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PMID:[Prenatal differential diagnosis in elevated alpha-fetoprotein concentration in the amniotic fluid (author's transl)]. 617 38

A quantitative method for cholinesterases in amniotic fluid using the non-specific substrate alpha naphthyl acetate and the cholinesterase-specific inhibitor, eserine, is described. This assay was used to test 671 samples of amniotic fluid. The diagnoses for fetal ONTDs, based on the levels of AChE + ChE, were compared with those made for the same samples by the AFP method. Correct diagnoses were made by both methods with amniotic fluid from 35 women carrying fetuses with ONTDs and 631 carrying normal fetuses. There were five false-positive test results for normal fetuses by both methods when the cut-off points were 5 standard deviations above the mean for AFP and above the upper limit of the normal range (7.5 milliunits) for cholinesterase (AChE + ChE). None of the false-positive samples from either method had the acetylcholinesterase band of activity characteristic of ONTDs after gel electrophoresis. In addition to the above 671 samples, 37 pregnancies with serious fetal abnormalities other than ONTDs were tested. Two were identified by both the AFP and AChE + ChE methods, two more by AFP assay and one other by the AChE + ChE assay.
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PMID:Measurement of cholinesterases in amniotic fluid using alpha naphthyl acetate as substrate: a possible initial test for prenatal diagnosis of open neural tube defects. 618 37

Under sodium pentobarbital anesthesia, the superior cervical ganglia of cats were preganglionically denervated bilaterally. The following day cats were reanesthetized, the external carotid and lingual arteries were ligated bilaterally, and the right common carotid artery was infused for 24 hr with an extract prepared from cat brain, spinal cord, and sciatic nerves, with and without the incorporation of aprotinin, an inhibitor of proteases. They were sacrificed 48 hr after denervation, and the acetylcholinesterase (acetylcholine acetylhydrolase, EC 3.1.1.7) and butyrylcholinesterase (acylcholine acylhydrolase, EC 3.1.1.8) contents of the superior cervical ganglia were compared with those of similarly denervated control ganglia. Both types of extract produced a significant reduction in the loss of both enzymes from the superior cervical ganglia, as did infusions of aprotinin alone. These findings demonstrate the presence of an endogenous neurotrophic factor for the maintenance of ganglionic acetylcholinesterase and butyrylcholinesterase. Its possible mechanisms of action, and those of aprotinin, are discussed.
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PMID:Demonstration of a neurotrophic factor for the maintenance of acetylcholinesterase and butyrylcholinesterase in the preganglionically denervated superior cervical ganglion of the cat. 619 Jan 71

Acetylcholinesterase (EC 3.1.1.7.; AChE) and butyrylcholinesterase (EC 3.1.1.8.; BuChE) from chicken muscle exist as sets of structurally homologous forms with very similar properties. The collagenase sensitivity and aggregation properties of the 'heavy' forms of both enzymes indicate that they possess a collagen-like tail, and their stepwise dissociation by trypsin confirms that they correspond to triple (A12) and double (A8) collagen-tailed tetramers. In addition to this dissociating effect, trypsin digests an important fraction of the catalytic units of AChE, in a progressive manner, removing as much as 30% of the enzyme's mass, without inactivation of the tetramers and of the tailed molecules. The trypsin-modified AChE forms closely resemble the corresponding mammalian AChE forms in their hydrodynamic properties. It is not known whether the trypsin-digestible peptides, which do not appear to be involved in the ionic or hydrophobic interactions of the enzymes, are a fragment of the catalytic subunit or whether they constitute distinct polypeptides.
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PMID:The quaternary structure of chicken acetylcholinesterase and butyrylcholinesterase; effect of collagenase and trypsin. 625 92

The present contribution deals with histochemical mapping of acetylcholinesterase, butyrylcholinesterase and non-specific esterase in the rhombencephalon and mesencephalon of the turtle (L. punctata). The study reveals that all the neurons of this species are strongly positive for AChE, irrespective of their sensory or motor nature. The enzyme is localized in cell bodies and dendritic processes, while the axons are completely negative. Thus its presence in the fibrous components is not seen except in the superficial layers of optic tectum. Non-specific esterase activity is quite prominent in all the neurons, while the neuropil is weakly positive in most of the nuclei with a few exceptions. The blood vessels are strongly positive throughout the area. In sharp contrast to these enzymes. BChE is completely missing in all the constituents.
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PMID:Topographical differences of carboxylic esterases in the rhombencephalon and mesencephalon of the turtle (Lissemys punctata granosa). 650 70

The catalytic efficiency of the field mouse (Mus booduga) brain acetyl cholinesterase (AChE, EC 3.1.1.7) was significantly (P less than 0.001) decreased probably through the reduction in the active site density of the enzyme content and elevation in the activation energy (delta E) requirements during repeated hexachlorophene (HCP) treatment. Fall in the activity potential of AChE may account for the interference of HCP or its reactive metabolites with the acetylcholine (ACh)-AChE system and deserve consideration in contributing to the neurotoxicity.
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PMID:Catalytic potential of field mouse Mus booduga brain acetylcholinesterase during repeated hexachlorophene treatment. 650 93

The source of butyrylcholinesterase (acylcholine acylhydrolase, EC 3.1.1.8) in the ganglion cells of the cat superior cervical and ciliary ganglia has been elusive, inasmuch as the enzyme is present in high concentrations in the neuropil, where it is confined largely to the dendritic and perikaryonal plasma membranes, but appears to be absent from the perikarya. In the present study, ganglionic butyrylcholinesterase was near-totally inactivated by the injection of tetramonoisopropyl pyyrophosphoramide (6.0 mumol/kg of body weight) intravenously. During the ensuing 72 hr, the regenerating enzyme became detectable by the copper thiocholine histochemical method in the somata of essentially all ganglion cells and in the neuropil. Results were similar in preganglionically denervated superior cervical ganglia and in normal ciliary ganglia. These findings suggest (i) that butyrylcholinesterase indeed is synthesized in the ganglion cell perikarya (presumably, the rough endoplasmic reticulum) and transported extremely rapidly to more peripheral cellular sites and (ii) that the synthesis is largely independent of control by any neurotrophic factor provided by the preganglionic axonal terminals. Similar studies were conducted in the rat. In this species, in contrast to the cat, the somata of essentially all ganglion cells of the superior cervical ganglion contain various but at least moderate concentrations of acetylcholinesterase (acetylcholine acetylhydrolase, EC 3.1.1.7) and propionylcholinesterase (acylcholine acylhydrolase, EC 3.1.1.8). After injection of tetramonoisopropyl pyrophosphoramide, propionylcholinesterase reappeared in the ganglion cell somata before its accumulation in the neuropil, as would be expected.
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PMID:Identification of the probable site of synthesis of butyrylcholinesterase in the superior cervical and ciliary ganglia of the cat. 657 57

The usefulness of a cholinesterase assay and electrophoresis in the prenatal diagnosis of neural tube defects was investigated in amniotic fluids from 1,512 women. The assay used a alpha-naphthyl acetate as substrate and measured the combined activity of the enzymes acetylcholinesterase (AChE, E.C. 3.1.1.7) and cholinesterase (ChE, E.C. 3.1.1.8); the activity of both enzymes was raised in amniotic fluid from women carrying open NTDs. The alpha-naphthyl acetate assay distinguished fetuses with neural tube defects from normal fetuses more effectively than assays using acetylthiocholine as substate. A perfect score could be obtained on the sample tested when both enzyme assay and electrophoresis were done on those samples with activity greater than or equal to 4 mU. There was no correlation between gestational age between 13-21 weeks and activity of AChE + ChE (r = 0.03). The electrophoretic band of AChE activity proved to be a valuable diagnostic adjunct to both AFP or the AChE + ChE assay. A similar band or AChE activity was seen in adult brain and intestine but not in kidney, heart, liver, or lung, or in sera from women carrying normal or NTD fetuses.
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PMID:Prenatal diagnosis of neural tube defects using the cholinesterases. 664 92

Daily dermal administration for 90 days of 0.01 to 10 mg/kg of O-ethyl O-4-nitrophenyl phenylphosphonothioate (EPN) technical grade (85%) in acetone (0.1 ml) on the unprotected back of the neck produced delayed neurotoxicity. Hens given 2.5 to 10 mg/kg daily doses also received daily doses of atropine sulfate for 5 or 6 days to protect against cholinergic acute toxicity. Severity of the clinical condition depended on the concentration of the daily dermal dose of EPN; i.e., while hens given small doses showed only ataxia, those treated with large doses progressed to paralysis and died. The most consistent histopathologic alteration was the degeneration of axons and myelin in the spinal cord which was identical to that found in positive control hens that received daily dermal doses of 5 or 10 mg/kg tri-o-cresyl phosphate (TOCP). Some of the hens treated daily with the smallest tested dose of EPN (0.001 mg/kg) which did not show clinical signs of delayed neurotoxicity showed equivocal histological changes in the spinal cord. EPN and TOCP treatments had a more profound effect on the activity of plasma butyrylcholinesterase than that of brain acetylcholinesterase (AchE). by contrast O,O,-diethyl O-4-nitrophenyl phosphorothioate (parathion) was more inhibitory to brain AChE. Negative control hens that were treated with 90 daily dermal doses of 1 mg/kg of parathion initially showed leg weakness followed by recovery. A group of hens that received the same volume of acetone (0.1 ml) daily remained normal.
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PMID:Effect of subchronic dermal application of O-ethyl O-4-nitrophenyl phenylphosphonothioate on producing delayed neurotoxicity in hens. 668 63


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