Subacute poisoning of mice with deltamethrin produces memory impairment, reduced locomotor activity, liver damage and changes in blood morphology in the mechanism of oxidative stress

Background: Deltamethrin (DEL) is a synthetic pyrethroid (PYR) insecticide, potent neurotoxicant. The current investigation was envisaged to explore behavioral, biochemical and morphologic effects of subacute poisoning with DEL in mice and to find one common mechanism of these changes. Methods: Mice were daily injected ip with different doses of DEL: 8.3, 20.75 or 41.5 mg/kg bw for 28 days. Their memory retention in passive avoidance task (PA), fresh spatial memory in a Y-maze and locomotor activity were measured once weekly. On day 29, blood morphology, alanine transaminase (ALT) activity and creatinine concentration in the blood sera, superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities were measured in the livers and kidneys. Livers were examined with light microscopy. Results: Significant impairment of memory retention was recorded on day 2, 7 and 28 after exposure to DEL. Fresh spatial memory was significantly impaired by the highest dose of DEL on day 1, 14 and 28. Locomotor activity was reduced at every stage of experiment in all the groups exposed to DEL. In the animals exposed to the highest dose of DEL activities of alanine transaminase (ALT) and SOD were elevated, GPx was reduced, lymphocyte infiltrates were detected in the livers and there were changes in blood morphology. Conclusion: The results obtained indicate that liver and bone marrow, apart from the central nervous system (CNS) are damaged in the course of subacute poisoning with DEL. The possible common mechanism of the damage is oxidative stress. (C) 2014 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier Sp. z o.o. All rights reserved.