Interactions of the Organophosphates Paraoxon and Methyl Paraoxon with Mouse Brain Acetylcholinesterase
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منابع مشابه
Interactions of rat brain acetylcholinesterase with the detergent Triton X-100 and the organophosphate paraoxon.
Inhibition of the critical enzyme acetylcholinesterase (E.C. 3.1.1.7) with subsequent cholinergic crisis is the mechanism of acute toxicity of the organophosphorus insecticides (B. E. Mileson et al., 1998, Toxicol. Sci.41, 8-20). Consequently, measurement of acetylcholinesterase activity is important for evaluating the mammalian toxicity of this commonly used class of insecticides. While mammal...
متن کاملConcentration-dependent kinetics of acetylcholinesterase inhibition by the organophosphate paraoxon.
For decades the interaction of the anticholinesterase organophosphorus compounds with acetylcholinesterase has been characterized as a straightforward phosphylation of the active site serine (Ser-203) which can be described kinetically by the inhibitory rate constant k(i). However, more recently certain kinetic complexities in the inhibition of acetylcholinesterase by organophosphates such as p...
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Acetylcholinesterase (AChE) is an important enzyme in the control of the neuronal action potential and sensitive to organophosphate inhibition. Brain fish AChE is less sensitive to organophosphate inhibition than AChE from terrestrial animals, although this sensitivity is variable among species and has not yet been fully evaluated in fish species. In this setting, inhibition kinetic constants f...
متن کاملComparison of chlorpyrifos-oxon and paraoxon acetylcholinesterase inhibition dynamics: potential role of a peripheral binding site.
The primary mechanism of action for organophosphorus (OP) insecticides, like chlorpyrifos and parathion, is to inhibit acetylcholinesterase (AChE) by their oxygenated metabolites (oxons), due to the phosphorylation of the serine hydroxyl group located in the active site of the molecule. The rate of phosphorylation is described by the bimolecular inhibitory rate constant (k(i)), which has been u...
متن کاملNovel bisquaternary oximes--reactivation of acetylcholinesterase and butyrylcholinesterase inhibited by paraoxon.
Four novel bisquaternary aldoxime cholinesterase reactivators differing in their chemical structure were prepared. Afterwards, their biological activity was evaluated for their ability to reactivate acetylcholinesterase (AChE; EC 3.1.1.7) and butyrylcholinesterase (BuChE; EC 3.1.1.8) inhibited by paraoxon. Their reactivation activity was compared with standard reactivators--pralidoxime, obidoxi...
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ژورنال
عنوان ژورنال: Toxicological Sciences
سال: 2000
ISSN: 1096-0929
DOI: 10.1093/toxsci/58.1.118