Tehran University of Medical Sciences Acta Medica Iranica 0044-6025 35 1-2 1997 06 15 45 48 M. Abdollahi. Y. Behmanesh M. Akhgari 2015 09 28 Organophosphorus compounds are known to inhibit the esteratic site of acetylcholinesterase by phosphorylation. The phosphorylated esteratic site of acetylcholinesterase undergoes hydrolytic regeneration at a slow or negligible rate. Nucleophilic agents such as hydroxytamine, hydroxamic acids, and oximes reactivate the enzyme more erapidfy than does spontaneous hydrolysis. The red cell cholinesterose activity was assayed using dithio bis-2-nitrobenzoic acid (DTNB) commonly known as Ellman's reagent. The principle of this assay method is the rate of hydrolysis of acetylthiocholine (substrate) by a red celt suspension. Thiocholine that is produced, forms a yellow complex, when EUman's reagent (DTNB) is used in the assay. This was tested in vitro in lysed erythrocyte samples of 35 healthy persons who had no known exposure to cholinesterose inhibitors, after the observation of immediate increase in absorption of light at 440 nm. All of data were statistically analyzed using one-way ANOVA and student t-test. A value of p https://acta.tums.ac.ir/index.php/acta/article/view/1717 https://acta.tums.ac.ir/index.php/acta/article/download/1717/1710