Acetyl cholinesterase (AChE) and butyryl cholinesterase (BChE) are two known enzymes in the body with ability to hydrolyze acetylcholine. While AChE plays crucial role in acetylcholine mediated neurotransmission, BChE is secreted from livers to plasma and biological role of the enzyme is not fully understood [1]. The both cholinesterases are very sensitive to inhibition by nerve agents such as ...

The introduction of controlled self-assembly into living organisms opens up desired biomedical applications in wide areas including bioimaging/assays, drug delivery, and tissue engineering. Besides the enzyme-activated examples reported before, controlled self-assembly under integrated stimuli, especially in the form of sequential input, is unprecedented and ultimately challenging. This study r...

Cholinesterase activity in human serum was measured calorimetrically and compared to values obtained with the spectrophotometric method of Rappaport et al. [Clin. Chim. Acta 4, 227 (1959)]. The response of the calorimeter upon mixing serum with acetylcholine corresponded to the cholinesterase activity of the serum, the thermogram peak height being linearly related to enzyme activity at serum di...

Cholinesterase (ChE) activity in birds is subject to interspecific and intraspecific species variations. Factors that influence enzyme activity have to be taken into account in order to obtain an accurate estimation of cholinesterase inhibition due to pesticide exposure in wild birds. This study evaluates variation of plasma cholinesterase activity in clay-colored robin (Turdus grayi) in relati...

Fenvalerate is a synthetic pyrethroid , widely used due to its high effective and low mammalian toxicity. Fenvalerate, dose equivalent to LD25 was administered orally for acute exposure and dose equivalent to LD5 for subchronic & chronic exposure to Wistar rats. Toxic effect of Fenvalerate observed in serum Lypase, alanine aminotransferase (ALT), aspartate aminotransferase (AST), Cholinesterase...

We report a case of prolonged neuromuscular block after administration of mivacurium 0.2 mg kg-1 to a 16-yr-old patient where the duration of block was 2.5 h. The interesting points in this case were that the patient had homozygous atypical plasma cholinesterase deficiency (both parents had a normal phenotype) following liver transplantation. Investigations showed low plasma cholinesterase acti...

V,,,, and K,,, values with twenty-five “atypical” and thirty-seven “usual” cholinesterase human sera were determined for the cholinesterase substrates procaine, tetracaine, benzoylcholine, o-nitrophenylbutyrate, cu-naphthylacetate and aspirin. Aspirin was demonstrated to be a substrate for serum cholinesterase. For each of these substrates the ratio of V,,substrate to V,,,, benzoylcholine was f...

The mechanism of enzyme-inhibitor-substrate reactions has been analyzed from a theoretical standpoint and illustrated by data from the system cholinesterase-physostigmine-acetylcholine. This treatment is by no means limited to a single system but should be generally applicable to others of similar type. Competitive enzyme-inhibitor-substrate systems show the same characteristic "zones of behavi...

Carbaryl is a carbamate insecticide. Like all members of this chemical family, it inhibits the action of an enzyme that is an essential component of insect, fish, bird, and mammal nervous systems. The enzyme, acetyl cholinesterase (AChE), controls the chemical reaction that transforms acetylcholine into choline after acetylcholine has been used to transmit nerve impulses across the junctions be...

A South African Afrikaans speaking family is reported in which a new high activity plasma cholinesterase variant was found to occur in the mother and son. The variant has the same electrophoretic mobility as the "usual' enzyme, but greater heat stability. Its higher specific activity is associated with a normal number of enzyme molecules. The variant may be inherited as a dominant trait, though...