Efficacy of 2-PAM, TMB-4, HI-6, and Toxogonin in Reactivation of Immobilized Acetylcholinesterase Inhibited by Compound R-33

ABSTRACT

Efficacy of reactivators 2-PAM, TMB-4, HI-6, and toxogonin in reactivation of acetylcholinesterase inhibited by compound R-33 has been studied. The study was performed with acetylcholinesterase immobilized and stabilized on a cotton fabric and with an indicator paper with acetylthiocholine iodide and 5,5′-dithiobis(2-nitrobenzoic acid). The enzyme activity was determined by measurement of remission changes of the fabric surface, caused by reaction of the chromogenic reagent with products of enzymatic hydrolysis of the substrate.

The most potent of the reactivators studied was 2-PAM at concentrations 0.5 mg.cm⁻³ and 0.1 mg.cm⁻³. Effectivity of this reactivator was over 20%. At these concentrations, reactivator HI-6 was less effective. Efficacy higher than that of 2-PAM was observed only after 20 min at concentrations 0.05 mg.cm⁻³ and 0.01 mg.cm⁻³. For TMB-4 and toxogonin the reactivation values were about 10% after 10 min, whereas after 15 or 20 min these reactivators were ineffective.

KEYWORDS :

• Acetylcholinesterase
• Biochemical Reaction
• HI-6
• Inhibition
• Vx
• 2-PAM
• R-33
• Reactivation
• TMB-4
• Toxogonin