EFFECT OF COMBINED EXPOSURE OF DICHLORVOS AND MONOCROTOPHOS ON NEUROTRANSMITTERS AND ACETYLCHOLINESTERASE IN RAT

Organophosphate pesticides are associated with neurotoxicity. Organophosphates are cholinesterase-inhibiting chemicals used predominately as pesticides. These have played a very important role in sustainable production of food, animal feed and as protection against disease vectors. They are also used as chemical warfare agents (nerve agents). The effects of dichlorvos and monocrotophos on brain neurotransmitters are well established. The combined effect of organophosphates (dichlorvos and monocrotophos) was supposed to have synergistic or additive effect on brain neurotransmitters. Combined exposure of dichlorvos and monocrotophos has significant inhibition in acetylcholine esterase activity during both studies of 15 days and 30 days. Levels of nor-epinephrine, dopamine and serotonin (5-hydroxytryptamine) increased significantly in dichlorvos and monocrotophos exposed animals. However, the increase was more pronounced in monocrotophos alone exposed animals. Thus, contrary to hypothesis, the combined exposure to these toxicants did not produce more pronounced toxicity as compared to their individual exposure except in case of nor-epinephrine.