Effects Of Prenatal Exposure To Low-concentration Chlorpyrifos On The Neural Progenitor Cells And Telencephalon Development In Embryonic Mouse

Chlorpyrifos(CPF) is widely used pesticide currently. It has been confirmed that CPF can cause embryonic development damage and intelligence of adult offspring declined,but the mechanism is unclear. In this study, we explored the mechanism of progenitor cells damaged.First, we given 0、1、3、5mg/kg/d CPF to GD7.5-11.5 ICR mice, HE staining and Pax6 、 Tbr2 、 Tuj1 immunohistochemical staining were performed. We found that CPF decresed VZ(Vertricular zone, VZ)cells by 15.8% when the CPF concentration is 5mg/kg/d while less effect in other concentrations. CPF reduced the number of Pax6 and Tbr2 positive cells while no obvious effect in Tuj1 positive cells.Second, we given 5mg/kg/d CPF to GD14 ICR mice for 3 times and Brdu single injected. Then we performed Brdu immunohistochemical staining. We found CPF reduced the percentage of Brdu+ in the apical while increased in the basal in each time; GD7.5-11.5 ICR mice were exposed with 5mg/kg/d and Brdu injected at 9:00 in E14. Brdu immunohistochemical staining shows that CPF could also reduced the percentage of Brdu+ in the apical while increased in the basal in 3h.Finally, GD7.5-11.5 ICR mice were exposed with 5mg/kg/d, obtained embryos in E14, performed coronal sections of hippocampus. Hippocampal primordium cells in E12、14 and hippocampal cells in E18 were counted. We found CPF decresed the number of hippocampal primordium cells by 18.6% in E12, by 13.6% in E14 and hippocampal cells decreased by 21.6% in CA3 and 12.6% in DG in E18.Conclusively,CPF exposured at embryonic could reduce the speed of INM(Interkinetic nuclear migration, INM), inhibited the proliferation of progenitor cells, effect the development of lateral ventricles wall. CPF damages hippocampal primordium cells and hippocampal cells in embryonic. Our study provided embryonic structure for intelligent damaged in adulthood.