Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.1.1.8 (cholinesterase)
 12,691 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Within the hypoglossal nucleus large amounts of acetylcholinesterase (AChE) activity are present in all the neurons, whereas intracellular butyrylcholinesterase (BuChE) activity occurs only within a ventro-caudally situated cluster of cells. AChE activity within the neurons occurs mainly in the cisternae of the granular endoplasmic reticulum but there is some in the intermembranous space of the nuclear envelope and in the Golgi complexes. In the neuropil, reaction product is seen along some axonal and synaptic membranes. The distribution of BuChE in the ventro-caudal cells is identical with that of AChE except that BuChE activity is absent from the neuropil. The level of intraneuronal AChE activity falls rapidly during the first few days after axotomy. The fall is due partly to a dissolution and peripheral migration of the E.R. but also to a decrease in AChE content of the E.R. that remains. Return of staining begins in the 4th week and continues as the E.R. reassembles. Staining in the neuropil falls more slowly, but recovers less completely. The ventro-caudal group of cells shows the same kinds of change, but more dramatically. BuChE activity returns only erratically and never completely. The similarity in normal distribution, and in response to axotomy, of the two cholinesterases suggests that their functions are related.
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PMID:Cholinesterase activity in the hypoglossal nucleus of the rat and the changes produced by axotomy: a light and electron microscopic study. 113 98

15 acetoxyethylenammonium compounds are studied as substrates for acetylcholinesterase (ACE) from bovine erythrocytes and for butyrylcholinesterase (BCE) from horse serum. Substitution of methyl groups of the ammonium grouping with other radicals and incorporation of onium nitrogen in the cycle resulted in the decrease of the hydrolysis rate under the action of BCE and ACE, the effect of BCE being more pronounced. The rate of the hydrolysis of N-acetoxyethylene-N-methylpiperidine iodide in the presence of ACE was 65 times as much as in the presence of BCE. This compound is a new specific substrate of ACE. Dipropylmethyl derivative turned not to be a good substrate for both enzymes. Dibutylmethyl and pyridinic derivatives were not attacked by ACE and BCE. Kinetic analysis of the compounds listed is performed, taking account of non-productive sorbtion. Possible role of hydrofobic regions in the orientation of substrates on the active surface of ACE and BCE is discussed.
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PMID:[Cholinesterase hydrolysis of acetylcholine derivatives with different structures of the ammonium grouping]. 113 4

Kinetic analysis of the interaction of butyrylcholinesterase and the phosphoorganic inhibitor GT-161 [(C2H2O)2P(O)SC2H4+N(CH3)2C6H5-1-] is carried out. Short time incubations of an enzyme and an inhibitor (1-3 sec), even under commensurable concentrations, were shown to enable the rate constants of irreversible enzyme inhibition to be calcualted by the formula for pseudomonomoleuclar reactions. A simple analytical method for the estimation of the enzyme active sites concentrations is proposed.
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PMID:[Estimation of the irreversible inhibition reaction rate constants and of the concentration of cholinesterase active sites under commensurable concentrations of enzyme and inhibitors]. 120 70

Thirty-five patients with primary rhegmatogenous retinal detachments were followed for at least 6 months after scleral buckling procedures with subretinal fluid (SRF) drainage, in order to define factors influencing anatomic and visual outcome. Thirty-two cases were surgically reattached; three were not. Among the reattached cases, final visual acuity was poorer in patients with: older age; longer standing, more extensive detachments; detachment of the macula (with or without the development of a visible macular lesion); macular lesions; and higher SRF butyrylcholinesterase activity. These factors were themselves interrelated. Follow-up duration was only weakly related to final acuity, probably because of the long post-surgical follow-up. Phakic/aphakic status bore little relationship to final acuity. The type or timing relative to drainage of inflammation producing treatment was not related to final acuity.
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PMID:Prognosis of primary rhegmatogenous retinal detachments. 1. Associations between clinical detachment characteristics, subretinal fluid butyrylcholinesterase and visual outcome following scleral buckling procedures. 124 87

Enzymatic hydrolysis kinetics of benzoylcholine (BzCh), phehylpropionic acid choline ester (PK-157), suberic acid dicholine ester (D-6) and p-phenylenediacetic (PK-139), p-phenylenedipropionic (PK-154 and PK-155), p-phenylenediacryc (PK-150 and PK-151) and phtalic (PK-105) acids diaminoalkyl esters by horse blood serum butyrylcholinesterase (BuChE) was studied. Hydrolysis constants Km, V and Kss were estimated by means of different graphic methods. PK-157 ester turned to be highly specific selective substrate for BuChE, its V being 20 times as high and Km -- 20 times as low as those for acetylcholine (ACh). The highest V value was found for D-6 in the case of diesters. Hydrolysis of aromatic dicarbonic acids diesters was characterized with significantly lower V values (0.6-10.% of V for ACh) and extremely low Km values (approximately 10(-5) -- 10(-6) M). Substrate inhibition was observed under the hydrolysis of BzCh, PK-157, D-6 and all aromatic dicarbonic acids esters by BuChE. Formal kinetic analysis revealed that inactive complex, which formed in this case, corresponded to ES2 composition. The appearance of substrate inhibition for BuChE and its increasing are supposed to be due to the increase in the size and in the rigidity of the acyl part of the molecule in the number of substrates studied.
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PMID:[Kinetics of enzymatic hydrolysis of quaternary aminoalkyl esters of aromatic mono- and dicarboxylic acids by butyrylcholinesterase from horse serum]. 127 69

Reversible inhibition of acetylcholinesterase (AChE) from bovine erythrocytes and butyrylcholinesterase (BuChE) from horse blood serum by quaternary diaminoalkyl esters of suberic (D-6), p-phenylenediacetic (PK-139), p-phenylenedipropionic (PK-154 and PK-155), p-phenylenediacrylic (PK-150 and PK-151) and phthalic (PK-105) acids, was studied under the following incubation conditions: pH 7.5, 25 degrees C, 0.1 M KCl. The inhibition kinetics were of a mixed competitive-incompetitive type, the incompetitive component alpha'-having higher values for AChE (0.26-0.60) than for BuChE (0.10-0.20). Diester PK-150 selectively inhibited BuChE (Ki=3.0-10(-6) M); its Ki value for AChE was 4.0-10(-4) M. The other diesters had a stronger inhibitory effect on AChE than on BuChE. High values of alpha' observed during AChE inhibition cannot be interpreted in terms of interaction of those bisquaternary compounds with the anionic site of the acetylated active centre and are probably due to their sorbtion at the peripheral anionic sites. Incompetitive inhibition constants (K'i=Ki/alpha') of BuChE by the diesters PK-139, PK-154 and PK-150 were found to be values of the same order as substrate inhibition constants determined in the course of BuChE hydrolysis of these diesters. Incompetitive inhibition found for the esters studied and substrate inhibition during hydrolysis of these compounds are presumably due to the same mechanism.
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PMID:[Kinetics of reversible inhibition of cholinesterases by quaternary diaminoalkyl esters of aromatic dicarboxylic acids]. 127 77

The aim of this work was to evaluate a possible correlation between erythrocyte acetylcholinesterase activity (AChE) and membrane fluidity expressed by fluorescence polarization of--1,6--diphenyl 1,3,5--hexatriene (DPH). Blood samples of 34 Alzheimer's patients (18F and 16M) were obtained and haemoglobin concentration, haematocrit, plasma (butyrylcholinesterase, BuChE) and erythrocyte (AChE) esterase activities and fluorescence polarization after introduction of DPH in erythrocyte membrane have been determined. Results were compared with values obtained from blood samples of 34 apparently healthy volunteers with the same age variation (53-82 years). There was no correlation between AChE activity and fluorescence polarization in the control group nor in the patients' group. There was a significant negative correlation (r = -0.82; p < 0.001) between mean corpuscular hemoglobin concentration (MCHG) and erythrocyte acetylcholinesterase activity in Alzheimer's patients. This correlation suggests that any variation of internal globular viscosity (or MCHG) may indirectly affect AChE enzymatic activity and consequently contribute to the loss of interrelation between AChE activity and membrane lipid fluidity, verified in the present work. A biological marker for Alzheimer's disease diagnosis remains to be discovered.
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PMID:[Evaluation of blood esterases in Alzheimer's disease]. 129 53

A suitable enzyme sensor for the analysis of anticholinesterase compounds of pharmaceutical interest is described. It is based on the competitive inhibiting properties of these compounds on the enzyme butyrylcholinesterase and it is constituted by a hydrogen peroxide amperometric electrode modified by a superimposed Nylon membrane containing two chemically immobilized biological mediators (butyrylcholinesterase and choline oxidase). Some applications to the analysis of several pharmaceutical forms containing different compounds showing anticholinesterase activity are also reported and evaluated.
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PMID:Determination of compounds with anticholinesterase activity in commercial drugs by a new enzyme sensor. 129 77

We describe a method of detecting human DNA mutations with nonradioactive, biotinylated allele-specific oligonucleotide probes. This method can detect seven different mutations in the butyrylcholinesterase, cystic fibrosis, and N-acetyltransferase genes under identical assay conditions. This indicates that it may be used to detect mutations responsible for a wide variety of genetic diseases and pharmacogenetic conditions. The method involves first amplifying selected DNA fragments by the polymerase chain reaction and dot blotting the amplified DNA in duplicate onto small nitrocellulose squares. Each dot blot is then hybridized in individual wells containing a tetramethylammonium chloride solution with short biotinylated probes specific for either the normal or mutant allele. Successfully hybridized probes are detected by a simple colorimetric reaction using an avidin-alkaline phosphatase conjugate, which yields a very strong, clear signal. DNA from homozygous normal or mutant individuals hybridizes only to the normal- or mutant-specific probes respectively, while DNA from heterozygous individuals hybridizes equally well with both probes. These results can be easily interpreted to assign a genotype to the sample DNA. This method is amenable to automation, and may be useful in clinical laboratories for diagnosis of a wide variety of DNA mutations responsible for unusual reactions to drugs and environmental chemicals.
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PMID:Detection of human DNA mutations with nonradioactive, allele-specific oligonucleotide probes. 130 45

The elements of the cholinergic system (acetylcholinesterase and choline acetyltransferase) and butyrylcholinesterase were studied in human cortical capillary samples, brain-derived endothelial cell cultures and glial cell cultures. It was shown that the elements of the cholinergic system are present in the microvessels, but the choline acetyltransferase activity may be due to contamination with cholinergic nerve terminals since no choline acetyltransferase could be demonstrated in endothelial cell cultures. The present results revealed that the activity of acetylcholinesterase is reduced in the cortical endothelial cell cultures after longer culture times, while butyrylcholinesterase activity is not altered. In a system where endothelial cells were cocultured with embryonic human brain astroglial cells for 12 days in vitro, the acetylcholinesterase activity was increased 2-fold. These results support a glial influence on the enzyme activity of the cerebral endothelium.
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PMID:Glial cells in coculture can increase the acetylcholinesterase activity in human brain endothelial cells. 130 38


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