title: Selective cognitive impairments are related to selective hippocampus and prefrontal cortex deficits after prenatal chlorpyrifos exposure.
abstract: Prenatal exposure to chlorpyrifos (CPF) leads to cognitive impairments in adulthood. The cytoarchitectural basis is unclear. In the present study, we assessed the effects of prenatal CPF exposure on T-maze delayed alternation task and the win-shift/lose-shift responses associated with the morphology of the dorsal hippocampus (dHPC) and the medial prefrontal cortex (mPFC) in adult animals. Gestational ICR female mice were exposed to 0, 1 or 5mg/kg/d of CPF through gestational days 13-17. Behavioral experiments were performed on postnatal days (PD) 45-60 of the male and female offsprings; morphological samples were collected on PD 60. Our behavioral study results showed a gradual increase in the number of lose-shift errors on increased memory loads in the 5mg/kg/d CPF-treated males. A weak initial increase in the number of lose-shift errors was observed in the females. In all of the groups, no significant differences were observed in the number of win-shift errors and correct of the first choice. The morphological studies showed extensive condensed nucleus and enlarged intercellular spaces in the CA1 and DG sub-regions in the dHPC of the CPF-treated males and the DG sub-region of the CPF-treated females. The cell count was significantly reduced in these sub-regions. The morphological studies showed no obvious abnormalities at PrL and IL of mPFC in the CPF-treated males and females, but the cell count was reduced. Our findings suggest that prenatal CPF exposure at 5mg/kg/d induces selective cognitive impairments, which based on the morphological deficits in the dHPC and the mPFC.
authors: College of Biological and Environmental Engineering, Zhejiang University of Technology, 18 Chao-Wang Road, Hangzhou 310014, China. chxp@zjut.edu.cn
authors: Xiao-Ping
authors: XP
authors: Chen
authors: Wen-Zhen
authors: WZ
authors: Chen
authors: Fei-Shi
authors: FS
authors: Wang
authors: Jian-Xiang
authors: JX
authors: Liu
mesh_terms: D000818:Animals; D004390:Chlorpyrifos / Q000633:toxicity*; D003072:Cognition Disorders / Q000139:chemically induced* / Q000473:pathology; D005260:Female; D006624:Hippocampus / Q000187:drug effects* / Q000473:pathology; D007306:Insecticides / Q000633:toxicity*; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D017397:Prefrontal Cortex / Q000187:drug effects* / Q000473:pathology; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects / Q000139:chemically induced* / Q000473:pathology
chemical_list: D007306:Insecticides; D004390:Chlorpyrifos