For assaying plasma cholinesterase (EC 3.1.1.8) activity and phenotyping by means of dibucaine inhibition, we have compared a commercially available kit, in which butyrylthiocholine is used as substrate, with two reference methods, one using benzoylcholine and the other propionylthiocholine. With 50 different samples of three of the most common genetic variants, we could clearly differentiate t...

We have developed a succinyldicholine-based assay for serum cholinesterase (EC 3.1.1.8) to help establish whether patients with suspected sensitivity to drugs of this type have enzyme abnormalities that cannot be detected by conventional laboratory techniques. Although the method discriminates between cholinesterase activities of drug-sensitive and nonsensitive people as well as an assay involv...

Submitters: Albert A. Dietz, Herbert M. Rubinstein, and Tina Lubrano, Research and Medical Services, VA Hospital, Hines, III. 60141; and Departments of Biochemistry and Medicine, Loyola University Stritch School of Medicine, Maywood, III. 60153 Evaluators: Philip J. Garry, Department of Pediatrics, Children’s Hospital, Ohio State University, Columbus, Ohio 43205 Frank Madera-Orsini, Biochemistr...

1512 CLINICAL CHEMISTRY, Vol. 25, No. 8, 1979 brano, T., Colorimetric determination of serum cholinesterase and its genetic variants by the propionylthiocholine-dithiobis(nitrobenzoic acid) procedure. Selected Methods Clin. Chem. 8,41-46 (1977). 5. King, J., Studies on human serum cholinesterases. Ph.D. thesis, University of Glasgow, 1974. 6. Garry, P. J., Serum cholinesterase variants: Examina...

Serum pseudocholinesterase activity in pregnant women was assayed spectrophotometrically using either propionylthiocholine or suxamethonium as substrate. All patients had a normal phenotype as indicated by normal dibucaine and fluoride numbers. However, the mean cholinesterase activity was lower than in the general population. There was a negative correlation between cholinesterase activity and...

An acetylcholine hydrolyzing enzyme was prepared and purified (40 times) from dwarf bean hypocotyl hooks. The purity of the enzyme was proved by polyacrylamide gel electrophoresis. The molecular weight of the enzyme was determined to be 65,000 daltons. Enzyme activity was the highest at pH 8.0 and between 30 and 36 C. The enzyme had an apparent affinity constant (K(m)) for acetylcholine of 460/...

Four methods for measuring serum cholinesterase activity have been applied to sera of normal individuals and of patients shown to be sensitive to short-acting muscle relaxants of the succinyldicholine type. They have been assessed according to their ability to differentiate between sensitive and insensitive individuals on the basis of enzyme activity measurements alone. The method described, ba...

in this study, a commercially available kit in which propionylthiocholine is used as a substrate and a dibucaine solution to determine the variants of the enzyme were utilized. plasma cholinesterase activity of 151 patients who underwent different operations was measured during a period of six months. the mean±sd of the enzyme activity in 150 patients was 4.39±1.17 ku/l .. seventeen patients (1...

Organocatalysis, which is mostly explored for its new potential industrial applications, also represents a chemical event involved in endogenous processes. In the present study, we provide the first evidence that imidazole and imidazole derivatives have cholinesterase-like properties since they can accelerate the hydrolysis of acetylthiocholine and propionylthiocholine in a concentration-depend...

A method that overcomes the difficulties of the 240-nm benzoylcholine method for phenotyping plasma cholinesterases has been developed. After a timed reaction, under the same reaction conditions as in the classic procedure, choline is detected at 500 nm by use of choline oxidase coupled with the peroxidase/phenol/aminoantipyrine system. Cholinesterase activity measurements, calibrated by use of...