Study On Effects Of Low Concentration Of Chlorpyrifos Exposure On Embryonic Precursor Cell Culture In Vitro From Telencephalon And Long-Term Spacial Memory

Chlorpyrifos (CPF) is one of the widely used Organophosphate pest-icides, elicited developmental neurotoxicity. Although without obviously nervous system toxicity, the subtoxic dosage of CPF prenatal exposure could cause the impairment of neurogenesis stage, especially to embryo and infancy. This article assesses the influence of low concentration CPF prenatal exposure on the neural cells from mice telencephalon, explores the impairment of the offsprings’spatial memory when exposured CPF on pregnant mouse.This study includes:(1) assesses the effect of CPF to primary telenc-ephalic cell culture of mice. Telencephalic cell culture were prepared from E14fetal mice, dissociated cells were plated on24well plates. CPF dissolved in dimethyl sulfoxide was administered at dosages0μM、5μM、 10μM、20μM、30μM、50μM、100μM、and200μM in culture medium. Observed the morphologic change of neurospheres;(2)After24hr and48hr culture in vitro, we assessed the percentage of apoptosis detected by flow cytometry;(3)Divided randomly ICR mice into control(mg/(kg·d)) group and5mg/(kg·d) CPF group, each group had8male and female mice. The13th-17th pregnant mice were administered at dosages of0and5mg/(kg·d) group. We began Morris water maze test until postnatal80th day.In the experiment, we found that, after24hr culture of gradient CPF exposure, the cultured telencepholic cells sticked together and formed neurosphere clones. in0-30μM CPF, the morphology of neurosphere clones remain unchanged; in50μM CPF, the number of clones began decrease, until rarely observed in100μM and200μM. The percentage of apoptosis cells increased from from50μM CPF, after48hr culture, the percentage of apoptosis cells rapidly increased.There was difference that between female or male mice in the Morris water maze spatial memory capacity. The male mice showed better spatial memory capacity than female mice. In the next training times, this sex selective significance vanished. After CPF exposure, there was also difference between male mice and female mice, male CPF mice needed more time to find the platform under water than male CPF mice in training, along with the repeat times, the difference vanished. There was no difference between female CPF treatment mice and control mice.