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Ramsay RR, Tipton KF. Assessment of Enzyme Inhibition: A Review with Examples from the Development of Monoamine Oxidase and Cholinesterase Inhibitory Drugs. Molecules 2017; 22:E1192. [PMID: 28714881 PMCID: PMC6152246 DOI: 10.3390/molecules22071192] [Citation(s) in RCA: 118] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2017] [Revised: 07/10/2017] [Accepted: 07/11/2017] [Indexed: 11/16/2022] Open
Abstract
The actions of many drugs involve enzyme inhibition. This is exemplified by the inhibitors of monoamine oxidases (MAO) and the cholinsterases (ChE) that have been used for several pharmacological purposes. This review describes key principles and approaches for the reliable determination of enzyme activities and inhibition as well as some of the methods that are in current use for such studies with these two enzymes. Their applicability and potential pitfalls arising from their inappropriate use are discussed. Since inhibitor potency is frequently assessed in terms of the quantity necessary to give 50% inhibition (the IC50 value), the relationships between this and the mode of inhibition is also considered, in terms of the misleading information that it may provide. Incorporation of more than one functionality into the same molecule to give a multi-target-directed ligands (MTDLs) requires careful assessment to ensure that the specific target effects are not significantly altered and that the kinetic behavior remains as favourable with the MTDL as it does with the individual components. Such factors will be considered in terms of recently developed MTDLs that combine MAO and ChE inhibitory functions.
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Affiliation(s)
- Rona R Ramsay
- Biomedical Sciences Research Complex, University of St Andrews, St Andrews KY16 8QP, UK.
| | - Keith F Tipton
- School of Biochemistry and Immunology, Trinity College, Dublin 2, Ireland.
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2
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Mutch E, Blain PG, Williams FM. Interindividual Variations in Enzymes Controlling Organophosphate Toxicity in Man. Hum Exp Toxicol 2016; 11:109-16. [PMID: 1349216 DOI: 10.1177/096032719201100209] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
1 Interindividual variations in an unexposed population have been defined for five enzymes involved in organophosphate (OP) toxicity. The enzymes measured were: red blood cell acetylcholinesterase (AChE), lymphocyte neuropathy target esterase (NTE), serum cholinesterase (ChE), serum paraoxonase and serum arylesterase. 2 AChE and arylesterase were normally distributed in the population whilst the distribution of NTE, ChE and paraoxonase deviated significantly from normal. 3 Assay precision and intra-individual variability were measured for each of the enzymes; the effect on interindividual variation was assessed. 4 Variations in enzyme activities between individuals could have profound effects on susceptibility to OP toxicity. Prior determination of these enzymes may be predictive of susceptibility. 5 Lymphocyte NTE has some limitations as an indicator of exposure to neurotoxic OPs.
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Affiliation(s)
- E Mutch
- Toxicology Unit, Medical School, Newcastle University, UK
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3
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Spencer JD, Rushton D, Allen KR. A simple liquid chromatography linked to tandem mass spectrometry method for measurement of serum cholinesterase activity using succinylcholine as substrate. Ann Clin Biochem 2010; 47:217-22. [DOI: 10.1258/acb.2010.009169] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Background Individuals who are unable to metabolize the short-acting muscle relaxant succinylcholine due to abnormal cholinesterase activity are currently investigated via spectrophotometry using artificial substrates and enzyme inhibitors. Methods have been described using succinylcholine as substrate but with measurement of the product choline. However, choline may be released from other endogenous substrates within the serum. Direct measurement of the in vitro metabolism of succinylcholine as substrate may provide a better indication of the in vivo situation with regard to cholinesterase status. Methods The rate of in vitro metabolism of succinylcholine by cholinesterase was measured using liquid chromatography linked to tandem mass spectrometry (LC-MS/MS). A comparison was made using serum samples in which cholinesterase activity had been measured using propionylthiocholine as substrate and phenotyped by enzyme inhibitor studies. Results A good correlation ( r = 0.9, P < 0.0001) was found between cholinesterase activity measured by LC-MS/MS using succinylcholine as substrate compared with propionylthiocholine as substrate measured spectrophotometrically. All serum samples with a cholinesterase activity of <1 IU/L, as measured using succinylcholine as substrate, were considered to be at increased risk of succinylcholine sensitivity. These latter results correlated well to the atypical phenotypes. Conclusions A simple and fast LC-MS/MS technique for the measurement of cholinesterase activity using succinylcholine as substrate has been described. This method clearly identifies patients at risk of prolonged apnoea following succinylcholine administration and compares favourably with existing spectrophotometric methods using artificial substrates.
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Affiliation(s)
- Jennifer D Spencer
- Department of Clinical Biochemistry, Leeds Teaching Hospitals NHS Trust, Britannia House, Morley, Leeds LS27 ODQ, UK
| | - David Rushton
- Department of Clinical Biochemistry, Leeds Teaching Hospitals NHS Trust, Britannia House, Morley, Leeds LS27 ODQ, UK
| | - Keith R Allen
- Department of Clinical Biochemistry, Leeds Teaching Hospitals NHS Trust, Britannia House, Morley, Leeds LS27 ODQ, UK
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Edwards JW, Lee SG, Heath LM, Pisaniello DL. Worker exposure and a risk assessment of malathion and fenthion used in the control of Mediterranean fruit fly in South Australia. ENVIRONMENTAL RESEARCH 2007; 103:38-45. [PMID: 16914134 DOI: 10.1016/j.envres.2006.06.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2005] [Revised: 06/05/2006] [Accepted: 06/09/2006] [Indexed: 05/11/2023]
Abstract
In 2001, an outbreak of Mediterranean fruit fly in Adelaide was controlled by South Australian Government workers applying organophosphorus insecticides (OPs) to domestic gardens. Residents made claims of adverse effects associated with allegations that worker application practices were poor and led to contamination of homes, residents and pets. The concerns led to a Parliamentary enquiry, the suspension of OP applications for fruit fly control, and the investigation of alternative methods of combating fruit fly in metropolitan Adelaide. The extent of exposure of workers and residents was not estimated. This paper describes a simulated application of the OPs concerned (fenthion and malathion) with measurements of potential exposure through inhalation, dermal contact and deposition of pesticides on surfaces. The data were used as part of a toxicological risk assessment to determine the likely impact of the use of these insecticides. Malathion, used as a 1% suspension in a protein bait mixture, was found to have little potential for airborne exposure, although some workers were found to have up to 0.315 microg/cm(2) malathion deposited on overalls (principally on forearms) and over 500 microg deposited on liner gloves and hats, respectively. Risks to workers and residents were low, with exposures likely to be a small fraction of the acceptable daily intake. Fenthion, used as a 0.05% foliar cover spray, was found between 0.02 and 0.23 mg/m(3) in air 10 m downwind from spray activity and was unlikely to pose a significant risk to residents, since exposures were of short durations of up to 20 min. Personal air samples of spray workers averaged 0.55 mg/m(3) (Workplace Exposure Standard 0.20mg/m(3)). Since workers were usually engaged in spraying for a large proportion of the day, this demonstrates the need for respiratory protective equipment. Maximum deposition of fenthion on workers overalls ranged from 0.06 to over 0.20 microg/cm(2), although little was found on gloves and hats, suggesting workers were skilled in avoiding the plume of overspray. Dialkyl phosphates (metabolites of OP insecticides) were not detected in urine of workers, and there were no changes observed in serum cholinesterase (SChE) enzyme activities 24h following the simulation. These data suggest absorption of OP insecticides by workers was negligible. Deposition on surfaces 5 and 10 m downwind ranged from none detected to 145 microg/cm(2), suggesting that exposure of residents and children in contact with contaminated surfaces (such as garden furniture or play equipment) is possible. Estimates of the potential dermal intake of fenthion by children from contaminated surfaces suggested that risks of acute and chronic effects are slight, since exposures may occur for short periods at intervals of approximately 10 days during fruit fly outbreaks.
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Affiliation(s)
- John W Edwards
- Department of Environmental Health, School of Medicine, Flinders University, GPO Box 2100, Adelaide, SA 5001, Australia.
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Gin T, Derrick JL, Chan MTV, Chui PT, Mak TWL. Postpartum Patients Have Slightly Prolonged Neuromuscular Block After Mivacurium. Anesth Analg 1998. [DOI: 10.1213/00000539-199801000-00016] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Gin T, Derrick JL, Chan MT, Chui PT, Mak TW. Postpartum patients have slightly prolonged neuromuscular block after mivacurium. Anesth Analg 1998; 86:82-5. [PMID: 9428856 DOI: 10.1097/00000539-199801000-00016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
UNLABELLED Postpartum patients have decreased plasma cholinesterase activity, which may slow the metabolism of mivacurium. We compared the duration of a mivacurium neuromuscular block in 11 women undergoing postpartum tubal ligation 36-99 h after delivery with that in 11 control women undergoing gynecological surgery. Anesthesia was induced with propofol and fentanyl and maintained with propofol and nitrous oxide. Neuromuscular block was monitored by electromyography, and the ulnar nerve was stimulated transcutaneously using a train-of-four pattern. Patients received a bolus dose of mivacurium 0.15 mg/kg. The median (range) duration of neuromuscular block until 25% recovery of the first twitch response was longer in the postpartum group, 19.4 (15.6-25.2) min, compared with the control group, 16.3 (11.0-23.4) min (P = 0.04). The median (range) plasma cholinesterase activity was decreased in the postpartum group, 4.0 (0.1-5.5) kU/L, compared with the control group, 7.1 (6.2-10.0) kU/L (P < 0.001). The duration of neuromuscular block was inversely correlated with cholinesterase activity (Kendall rank correlation tau = -0.43, P = 0.005). The slight prolongation of neuromuscular block should not be significant clinically. IMPLICATIONS Postpartum patients have decreased amounts of the plasma cholinesterase enzyme. This would slow the metabolism of the muscle relaxant mivacurium. However, the duration of muscle paralysis is only prolonged by approximately 3 min, which would not normally cause any significant problems.
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Affiliation(s)
- T Gin
- Department of Anaesthesia and Intensive Care, Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, New Territories, Hong Kong.
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Ansermino JM, Burke MA, Upton PM, McVittie J, Blogg CE. Suxamethonium-induced muscle pains are not related to cholinesterase activity. Anaesthesia 1993; 48:1097-100. [PMID: 8285336 DOI: 10.1111/j.1365-2044.1993.tb07538.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
We have investigated the possibility of using the pre-operative measurement of cholinesterase activity to predict the postoperative development of myalgia following the administration of suxamethonium. Seventy-seven patients presenting for elective extraction of wisdom teeth were entered in the study. All patients received a standard anaesthetic regimen, including suxamethonium to facilitate tracheal intubation, and standardised postoperative analgesia. Myalgia was assessed postoperatively and no correlation between muscle pains and cholinesterase activity was found.
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Pariente F, Hernández L, Lorenzo E. 4-Aminophenyl acetate as a substrate for amperometric esterase sensors. Anal Chim Acta 1993. [DOI: 10.1016/0003-2670(93)80183-l] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Arnaud J, Brun H, Llobera R, Constans J. Serum cholinesterase polymorphism in France: an epidemiological survey of the deficient alleles detected by an automated micro-method. Ann Hum Biol 1991; 18:1-8. [PMID: 2009002 DOI: 10.1080/03014469100001352] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The polymorphism of the serum cholinesterase CHE 1 was determined using an automated micro-method. The procedure developed represents an improvement of the manual method and enabled us to study more than 2400 samples obtained in 15 different geographical areas in France. Four alleles were detected: CHE1* U, A, S and F. An exceptionally high frequency of an atypical variant (CHE1*A) was observed in the central part of France (Cevennes, Limousin and Dauphiné). The populations belonging to these areas are at particular risk in case of anaesthesia.
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Affiliation(s)
- J Arnaud
- CRPG/CNRS, Centre de Recherches sur le Polymorphisme Génétique des Populations Humaines, CHU de Purpan, Toulouse, France
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Proposed routine method for phenotyping of cholinesterase (CHE) locus E1 variants with butyrylthiocholine as substrate at 37 �C. Anal Bioanal Chem 1988. [DOI: 10.1007/bf00469286] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Abstract
We report the evaluation of a new commercially available assay system for determination of the catalytic activity of serum cholinesterase (EC 3.1.1.8) and application of the method to a centrifugal fast analyzer. Serum cholinesterase activity is determined at 30 degrees C using para-hydroxybenzoylcholine as substrate. This reaction is coupled to a second reaction using para-hydroxybenzoate hydroxylase (EC 1.14.13.2) as coupling enzyme. Enzyme activity is measured kinetically by monitoring the decrease in absorbance at 340 nm of NADPH in the second reaction. The procedure is precise and the results obtained from normal and pathological sera show good correlation with those obtained by the alternative procedures employing propionylthiocholine, butyrylthiocholine and benzoylcholine as substrates. The reference range for 700 healthy subjects was estimated to be 140-345 U/L (95% central range, determined non-parametrically), with significant difference between males and females (155-353 U/L for men and 134-323 U/L for women, p less than 0.001).
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Abstract
The measurement of cholinesterase activity in human serum is an important investigation, especially in patients suspected of poisoning with organophosphate insecticides, or those experiencing prolonged paralysis following treatment with the short acting muscle relaxant succinylcholine. Appropriate clinical management of affected individuals can only be instituted if enzyme activity is measured using a method capable of clear interpretation and phenotypic ascription of cholinesterase, ascertained by use of selected enzyme inhibitors, is reliable. This review considers factors which lead to significant cholinesterase abnormalities and advises on the techniques most appropriate to their investigation. It is concluded that no one method is suitable both for measurement of activity and determination of genotype. The use of propionyl thiocholine is recommended for the first procedure and benzoyl choline for the latter. Those laboratories in which a request for the assessment of cholinesterase status is an unusual event should make greater use of assistance from colleagues whose experience with the problem is greater.
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Uete T, Masui K, Miyauchi M. Comparison of substrates for measuring serum choline esterase activity in hepato-biliary disease. JOURNAL OF CLINICAL CHEMISTRY AND CLINICAL BIOCHEMISTRY. ZEITSCHRIFT FUR KLINISCHE CHEMIE UND KLINISCHE BIOCHEMIE 1985; 23:669-75. [PMID: 2999290 DOI: 10.1515/cclm.1985.23.10.669] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The efficacy of various substrates for measuring serum choline esterase for the evaluation of hepatic function was studied using o-toluoyl- and succinyl-choline, and acetyl, butyryl- and propionyl-thiocholine. In hepatic disease, the serum choline esterase activity with these substrates was decreased at a similar rate, showing no significant difference. In 78 - 84% of cases with hepatic cirrhosis the enzyme activity with these substrates was less than 50% of the average level of normal individuals, but in acute and chronic hepatitis only 4-9 and 12-14% of patients showed these lower values, respectively. The present study indicates the usefulness of sequential monitoring of serum choline esterase activity with any of these substrates for assessing hepatic disease, particularly cirrhosis, and for monitoring the course of hepatic disease.
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Turner JM, Hall RA, Whittaker M, Holder RL, Kricka LJ. Application of stepwise discriminant analysis in the phenotyping of plasma cholinesterase variants. Ann Clin Biochem 1985; 22 ( Pt 2):175-8. [PMID: 4004108 DOI: 10.1177/000456328502200213] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Discriminant function analysis has been applied to the results of activity and inhibitor measurements carried out on a series of 229 specimens using benzoylcholine and butyrylthiocholine as substrate. The discriminant function was more effective in differentiating cholinesterase genotypes than either a single test or a combination of two tests.
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Panteghini M, Bonora R. Evaluation of a new continuous colorimetric method for determination of serum pseudocholinesterase catalytic activity and its application to a centrifugal fast analyser. JOURNAL OF CLINICAL CHEMISTRY AND CLINICAL BIOCHEMISTRY. ZEITSCHRIFT FUR KLINISCHE CHEMIE UND KLINISCHE BIOCHEMIE 1984; 22:671-6. [PMID: 6512497 DOI: 10.1515/cclm.1984.22.10.671] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
We report the evaluation of a new commercially available assay system for the determination of serum pseudocholinesterase (EC 3.1.1.8) catalytic activity, and its application to a kinetic analyser. The assay is based on the colorimetric method of Okabe et al. (Clin. Chim. Acta 80, 87-94 (1977]: choline, liberated from benzoylcholine by pseudocholinesterase, is oxidized by choline-oxidase (EC 1.1.3.17) to betaine with the simultaneous production of hydrogen peroxide, which oxidatively couples with 4-aminoantipyrine and phenol in the presence of peroxidase to yield a coloured compound with maximal absorbance at 500 nm. The procedure not only has the advantage of being continuous, colorimetric and totally enzymatic but also appears to be precise (between-day analysis gives coefficient of variation between 3.5 and 5.6%) and accurate; the results obtained from normal and pathological sera show excellent correlation with those obtained by the alternative procedures employing propionylthiocholine, acetylthiocholine and butyrylthiocholine as substrates.
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Turner JM, Hall RA, Whittaker M, Kricka LJ. Effects of storage and repeated freezing and thawing on plasma cholinesterase activity. Ann Clin Biochem 1984; 21 ( Pt 5):363-5. [PMID: 6508207 DOI: 10.1177/000456328402100504] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Plasma cholinesterase activity, determined using either benzoyl choline or butyrylthiocholine as substrate, is stable for prolonged periods (greater than 12 months) when stored at -20 degrees C. Likewise, repeated freezing and thawing of plasma did not markedly affect cholinesterase activity.
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Whittaker M, Britten JJ. A comparison of some methods of phenotyping the plasma cholinesterase variants using benzoylcholine as substrate. Ann Clin Biochem 1981; 18:9-14. [PMID: 7259066 DOI: 10.1177/000456328101800103] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Five differential inhibitors of plasma cholinesterase have been compared using benzoylcholine as substrate. None of the inhibitors (dibucaine, NaF, NaBr, NaCl, or pancuronium dibutyryloxy bromide) could be used singly to resolve all the variants. Better resolution was obtained when two inhibitors were used in conjunction. Clear differentiation of all six genotypes was obtained only with the combined use of pancuronium dibutyryloxy bromide and sodium fluoride. The limitations of some of the parameters are discussed.
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Brown SS, Kalow W, Pilz W, Whittaker M, Woronick CL. The plasma cholinesteerases: a new perspective. Adv Clin Chem 1981; 22:1-123. [PMID: 7027759 DOI: 10.1016/s0065-2423(08)60046-3] [Citation(s) in RCA: 107] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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Abstract
Biochemical properties of plasma cholinesterase of significance to the anaesthetist are reviewed. The role of the genetic variants of the enzyme in suxamethonium sensitivity and hyperthermia are discussed with emphasis on the pregnant patient. Altered gene frequencies of the enzyme variants in some mental disorders is commented upon.
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Lam VM. Pseudo-cholinesterase of snake sera. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY. C: COMPARATIVE PHARMACOLOGY 1977; 58:129-31. [PMID: 23925 DOI: 10.1016/0306-4492(77)90092-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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23
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Price EM, Brown SS. Scope and limitations of propionylthiocholinesterase in the characterisation of cholinesterase variants. Clin Biochem 1975; 8:384-90. [PMID: 1204213 DOI: 10.1016/s0009-9120(75)94020-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
1. A manual procedure, using propionylthiocholine, for the determination of serum cholinesterase and its genetic variants has been assessed in respect of its precision and of its ability to classify the genetic variants of the enzyme. 2. It is shown that the propionylthiocholinesterase activity alone is a useful guide in identifying individuals who are likely to be sensitive to succinylcholine. 3. In phenotyping with dibucaine and fluoride, sera of phenotypes U and UF could not be distinguished from each other with confidence, but were distinguishable from sera of phenotype UA.
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Dietz AA, Rubinstein HM, Lubrano T, Hodges LK. Improved method for the differentiation of cholinesterase variants. Am J Hum Genet 1972; 24:58-64. [PMID: 5012693 PMCID: PMC1762147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
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25
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Das PK. Cause of the heterogeneity of 'silent' plasma cholinesterase variants. Biochem J 1971; 124:45P-46P. [PMID: 5130981 PMCID: PMC1177299 DOI: 10.1042/bj1240045pb] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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Das PK, Watts RL, Watts DC, Dimelow EJ. Distribution, specificity and function of some proteases, general esterases and cholinesterases from several species of starfish. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY. B, COMPARATIVE BIOCHEMISTRY 1971; 39:979-97. [PMID: 5132544 DOI: 10.1016/0305-0491(71)90122-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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Das PK, Watts RL, Watts DC. An altered erythrocyte acetylcholinesterase associated with hereditary muscular dystrophy in mice. Biochem J 1971; 123:24P-25P. [PMID: 5126884 PMCID: PMC1177026 DOI: 10.1042/bj1230024p] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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