Comparison between the Effects of Malathion and Deltamethrin to Cholinesterase Activity in Rabbits

Abstract

The evaluation of the inhibitory effect of malathion and the deltamethrin on cholinesterase activity in the blood plasma and brain in rabbits was measured by using modified Michel and Ellman methods together in order to confirm the results and to increase the accuracy of measurement have been measuring the cholinesterase activity in vitro and in vivo. Malathion concentrations ranged from(0.5 ــ 4 mM) when mixed with the blood plasma and the homogenize of the brain in vitro results significant inhibition in the cholinesterase activity and found highest of inhibition was 93% and 94% in the blood plasma and brain respectively, while deltamethrin concentrations ranged from(2.5ــ20 mM) results significant inhibition in the cholinesterase activity and highest percentage of inhibition was 54% and 48% in the blood plasma and brain respectively, and so when measuring cholinesterase using the Ellman method, but when using the modified Michel method the inhibition percentage when using malathion was 55% and 98% in the blood plasma and brain respectively, and when using deltamethrin ratio was 36% and 70% in the blood plasma and brain respectively. While when malathion administered orally in rabbits, with doses from (150ــ1200 mg/kg) results significant inhibition  in the cholinesterase activity and highest of inhibition when measuring by Ellman method was 84% and 88% in the blood plasma and brain respectively, while deltamethrin when administered orally with doses ranged from (12.5ــ100 mg/kg) the highest inhibition was 31% and 33% in the blood plasma and brain respectively, whereas when measured by using modified Michel method found highest inhibition when malathion administered orally 75% and 87% in the blood plasma and brain respectively, whereas when deltamethrin administered orally found highest inhibition 32 % and 45% in the blood plasma and brain respectively. From this study shows that malathion more influence on the cholinesterase activity than deltamethrin.