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1 Background cyhalothrin type II pyrethroid pesticides are neurotoxic is moderately toxic to humans and animals, a mild stimulating effect on the eyes. With contact and stomach action-based, and have some repellent effect, no sucking and fumigation; quick, long duration, the ability of rainwater leaching; spectrum insecticide. Regardless of the manner in which applied to crops, will be directly or indirectly into the soil, residues which pollute water and soil, enter the body through a variety of ways. Studies have shown that rats in the critical period of brain development before birth exposure at lower doses of pyrethroid insecticides (pyrethrins propylene), can lead to rat learning and memory dysfunction, leading to irreversible brain function in adulthood change effort Permethrin is commonly used in China as a pyrethroid pesticide, so its neurotoxicity caused can not be ignored. Widespread attention to acute pesticide poisoning, has also started to pay attention chronic low-dose exposure to toxic effects, but the long-term toxic effects of chronic pesticide exposure resulting neurodevelopmental toxicity has not been duly recognized and attention. (2) research purposes in postnatal critical period of brain development, with cyhalothrin exposure by oral gavage to mice to observe the neurobehavioral development situation; detecting the level of oxidative stress in brain and synapse-related protein expression, preliminary explore its possible mechanism. 3 research programs pups fifth day after birth (PND5) for the first exposure, every other day, exposed five (PND5-13). Detecting developmental neurobehavioral toxicity test in mice to measure cyhalothrin on offspring physiological development, physical movement and sensory-motor coordination and the impact; last administration (PND 13) after 24 h, the mice were killed, ice fast separation brain, cerebellum detect GSH, MDA and other indicators of oxidative stress, the right brain cortex, hippocampus, striatum for WESTERN detect the expression of synaptic proteins, left brain conventional fixed, paraffin-embedded, sliced, for immunization Histochemical examination. 4 results early exposure cyhalothrin can affect offspring body movement coordination and development, performance increases with the exposure dose, forelimb suspension, prolonged feeding reflex compliance (r = 0.97, P lt; 0.05); exposure period no other abnormalities in mice, mouse body weight, brain weight and other neurobehavioral development indicators in each group were not significantly different. Oxidative stress in cerebellar damage detection, 10mg/kg dose groups of mice GSH decreased (P lt; 0.05), MDA increased (P lt; 0.05). On mouse brain synaptic protein expression level detection can lead to glial fibrillary acidic protein (GFAP) in the hippocampus and cortex increased expression was statistically significant (P lt; 0.05), and there dose-related (males: r hippocampus = 0.986, r = 0.945 cortex, females: r hippocampus = 0.993, r = 0.969 cortex, both P lt; 0.05); β-tubulin Ⅲ type (Tuj) in various brain regions pups expression did not change significantly; growth-associated protein 43 (GAP-43) in male rats and female pups hippocampus hippocampus and cortex increased expression was statistically significant (P lt; 0.05), and has dose-related (males: r = 0.882 hippocampus, females: r hippocampus = 0.997, r cortex = 0.99, P lt; 0.05); synaptic protein Ⅰ (Synapsin Ⅰ) in the offspring of mice expressing various brain regions did not change significantly; postsynaptic dense protein 95 (PSD95) in ICR mice in the hippocampus, striatum and cortex of female mice decreased expression was statistically significant (P lt; 0.05), in addition to females outside the hippocampus were dose-related (males: r hippocampus = -0.991, females: r striatum = -0.996, r = -0.995 cortex, both P lt; 0.05). 5 Conclusion early postnatal exposure cyhalothrin limited number of times during the exposure will affect the pups tactile and motor coordination of development, there is oxidative stress on the cerebellum, and the cortex, hippocampus, striatum synaptic proteins expression to a certain extent, may affect the brain build synaptic connections.
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