title: Gestational-lactational exposure to Aroclor 1254 impairs radial-arm maze performance in male rats.
abstract: Developmental exposure to polychlorinated biphenyls (PCBs) has been associated with cognitive deficits in children. The current study assessed effects of gestational and lactational exposure to a commercial PCB mixture, Aroclor 1254 (A1254), on spatial learning and memory in rats, using the radial-arm maze (RAM). Pregnant Long-Evans females (10/dose group) were exposed to 0 or 6-mg/kg/day A1254 (po in corn oil) from gestation day (GD) 6 to weaning at postnatal day (PND) 21. After they reached adulthood, 1 male and 1 female from each litter were tested on a working/reference memory task using a 12-arm RAM. Eight of the 12 arms were baited, with the pattern of baited arms remaining the same on every trial for each rat. Compared to control males, the A1254-exposed males made significantly more working memory errors (2.15 +/- 0.13 and 3.20 +/- 0.18 errors +/- SEM for control and A1254 males, respectively) and reference memory errors (3.17 +/- 0.10 and 4.13+/-0.14 errors +/- SEM for control and A1254 males, respectively) on the RAM. In contrast, A1254-exposed females were not impaired relative to control females on the RAM. Drug challenges with dizocilpine (MK-801) and scopolamine did not differentially affect working or reference memory of control and exposed rats. These data suggest that perinatal exposure to A1254 may cause sex-specific deficits in spatial learning and memory, and that NMDA-mediated and muscarinic neurotransmission, as assessed with the drug challenges, were not markedly impaired in the A1254-exposed animals.
authors.affiliation: Neuroscience Program, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.
authors.forename: C S
authors.initials: CS
authors.lastname: Roegge
authors.forename: B W
authors.initials: BW
authors.lastname: Seo
authors.forename: K M
authors.initials: KM
authors.lastname: Crofton
authors.forename: S L
authors.initials: SL
authors.lastname: Schantz
mesh_terms: D000818:Animals; D000833:Animals, Suckling; D020111:Chlorodiphenyl (54% Chlorine) / Q000008:administration & dosage / Q000633:toxicity*; D016291:Dizocilpine Maleate / Q000633:toxicity; D018691:Excitatory Amino Acid Antagonists / Q000633:toxicity; D005260:Female; D008297:Male; D008431:Maternal-Fetal Exchange; D018782:Maze Learning / Q000187:drug effects*; D008570:Memory, Short-Term / Q000187:drug effects; D008892:Milk / Q000737:chemistry*; D011247:Pregnancy; D051381:Rats; D020318:Rats, Long-Evans; D012601:Scopolamine / Q000633:toxicity; D012727:Sex Characteristics
chemical_list: D018691:Excitatory Amino Acid Antagonists; D020111:Chlorodiphenyl (54% Chlorine); D016291:Dizocilpine Maleate; D012601:Scopolamine