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

Volume 7 (2009), No 4, p 201-206

Inhibition of blood cholinesterases by nerve agents in vitro

Jiri Bajgar, Daniel Jun, Kamil Kuca, Josef Fusek, Jana Zdarova Karasova, Jiri Kassa, Jiri Cabal, Vaclav Blaha

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

Received 17th June 2009.
Revised 8th September 2009.
Published online 12th November 2009.

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The bimolecular rate constants (ka) of inhibition were determined for cholinesterase in rat blood in vivo and three nerve agents in vitro. They were in the range of 105-106 M.min -1 with the highest value for VX (ka = 8.92 x 106), the next highest for soman (ka = 3.22 x 106) and the lowest for sarin (ka = 0.39 x 106), respectively. The inhibition rate is the same in vitro and in vivo; when the real inhibition in vivo and in vitro is compared, it is possible to assess the concentration of the nerve agent present in the blood stream. When administered intramuscularly it is about 70% of the dose administered.

whole blood cholinesterases; rat; nerve agents; inhibition in vitro

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