Effect of sub-chronic exposure to deltamethrin on neural behavior and expression of NMDA receptor in hippocampus of mice

Abstract

Objective To study the effect of sub-chronic exposure to deltamethrin(DM) on neural behavior and expression of NMDA receptor in hippocampus of mice. Methods 60 Female SPF Kunming mice were divided into 4 groups and given DM 60 days by gavage.Hot-plate, rotarod, grip strength, hing limb landing foot splay were used to examine the sensory and motor change of mice.Autonomic activity test was used for detecting the functional status of the central nervous system in mice. Passive avoidance test for detection of the behavior changes of learning and memory, and RQ-PCR was employed to measure the expression of NMDA receptor in hippocampus of mice. Results The behavior of sensory and motor of mice sub-chronic exposure to deltamethrin did not have changes significantly(P>0.05). In the test of autonomic activity test, the average of autonomic activity times were (93±18) times, (107±13) times, (105±22) times. Compared with the control group, the average of autonomic activity times in middle-and high-dose groups were increased significantly(P<0.05). The latent periods in poisoning groups were (175.4±38.4)s, (146.4±51.2)s, (132.3±45.0)s, and the error times were (0.7±0.3) times, (1.4±0.5) times, (1.8±0.9) times. Compared with the control group, latent periods of high-dose group were decreased and the error times of middle-and high-dose groups were increased significantly(P<0.05). Compared with the control group, the relative expression levels of NR1 and NR2A mRNA in hippocampus of middle and high-dose groups were increased significantly (P<0.05), and the relative expression level of NR2B mRNA in high-dose group was decreased significantly(P<0.05). Conclusion Sub-chronic exposure to DM could increase the excitability of mice, damage the function of learning and memory, and influence the expression of NMDA receptor in hippocampus of mice. Key words: Deltamethrin; Sub-chronic; Neural behavior; NMDA receptor