ISSN 1214-0287 (on-line)
ISSN 1214-021X (printed)

Volume 4 (2006), No 3, p 147-151

Reactivation of acetycholinesterase inhibited by the pesticide chlorpyrifos

Veronika Racakova, Daniel Jun, Veronika Opletalova, Kamil Kuca

Address: Kamil Kuca, Department of Toxicology, Faculty of Military Health Sciences, University of Defence, Trebesska 1575, 500 01, Hradec Kralove, Czech Republic

Received 4th January 2006.
Revised 2nd March 2006.
Published online 1st June 2006.

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Organophosphorus pesticides such as parathion or chlorpyrifos are substances used worldwide for agricultural purposes. These compounds are able to inhibit an enzyme acetylcholinesterase (AChE; EC by phosphorylation in its active site. AChE reactivators and anticholinergics are generally used as antidotes in the case of intoxication by these agents. In this work, the reactivation potency of nine structurally different AChE reactivators was tested in vitro. Chlorpyrifos was chosen as an appropriate member of the pesticide family. The result is that bisquaternary reactivators with two oxime groups in position four at the pyridinium rings (trimedoxime and K074) seem to be the most potent reactivators of chlorpyrifos-inhibited AChE.

acetylcholinesterase; reactivator; pesticide; organophosphate

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