title: Neurobehavioral effects, c-Fos/Jun expression and tissue distribution in rat offspring prenatally co-exposed to MeHg and PFOA: PFOA impairs Hg retention.
abstract: Exposure to methylmercury (MeHg) and perfluorooctanoic acid (PFOA) can occur simultaneously as both contaminants are found in the same food sources, especially fish, seafood, marine mammals and milk. The aim of this study was to assess the effects of exposure to MeHg (10 μg mL(-1) in drinking water) and PFOA (10 μg mL(-1) in drinking water) from gestational day 1 to postnatal day (PND) 21, alone and in combination, on neurobehavioral development and the expression of c-Fos/Jun in different brain regions in the offspring. Our findings showed that exposure to MeHg alone, and exposure to MeHg combined with PFOA significantly induced cliff avoidance reflexes and negative geotaxis reflexes. And these effects appeared to be greater following exposure to MeHg alone. MeHg and/or PFOA exposure did not significantly impair motor coordination functions, or cause significant changes in c-Fos expression in the hippocampus and cerebellum, and spatial learning tests were similar to those in the controls, thus it was impossible to determine whether combined exposure to MeHg and PFOA had any additional effects on both hippocampus and cerebellum regions. However, a significant increase in the frequency of line crossing was observed in rats treated with MeHg or PFOA alone, and there were no significant differences between the MeHg+PFOA-treated group and the controls, suggesting that PFOA was antagonistic to MeHg toxicity in the locomotor activity test. Co-exposure to MeHg and PFOA decreased all tissue Hg concentrations in pups compared to the group exposed to MeHg only, suggesting that PFOA impaired Hg retention in different tissues.
authors.affiliation: School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, China. jpcheng@sjtu.edu.cn
authors.forename: Jinping
authors.initials: J
authors.lastname: Cheng
authors.forename: Masatake
authors.initials: M
authors.lastname: Fujimura
authors.forename: Wenchang
authors.initials: W
authors.lastname: Zhao
authors.forename: Wenhua
authors.initials: W
authors.lastname: Wang
mesh_terms: D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects* / Q000502:physiology; D002210:Caprylates / Q000633:toxicity*; D005260:Female; D005466:Fluorocarbons / Q000633:toxicity*; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects; D048031:JNK Mitogen-Activated Protein Kinases / Q000378:metabolism*; D008297:Male; D018811:Maternal Exposure / Q000009:adverse effects; D008568:Memory / Q000187:drug effects; D008628:Mercury / Q000493:pharmacokinetics*; D008767:Methylmercury Compounds / Q000633:toxicity*; D009043:Motor Activity / Q000187:drug effects; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects / Q000378:metabolism* / Q000503:physiopathology; D016760:Proto-Oncogene Proteins c-fos / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D012018:Reflex / Q000187:drug effects; D014018:Tissue Distribution / Q000187:drug effects
chemical_list: D002210:Caprylates; D005466:Fluorocarbons; D008767:Methylmercury Compounds; D016760:Proto-Oncogene Proteins c-fos; C023036:perfluorooctanoic acid; D048031:JNK Mitogen-Activated Protein Kinases; D008628:Mercury