Impaired cued delayed alternation behavior in adult rat offspring following exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin on gestation day 15

Proteomic pathway analysis of the hippocampus in schizophrenia and bipolar affective disorder implicates 14-3-3 signaling, aryl hydrocarbon receptor signaling, and glucose metabolism: Potential roles in GABAergic interneuron pathology

“…AHR is a highly conserved transcription factor ubiquitously expressed in the brain, whose most potent ligand and activator is 2,3,7,8-tetra-chlorodibenzo-p-dioxin (TCDD), a common industrial pollutant (Abel and Haarmann-Stemmann, 2010). Rodents exposed to TCDD during neurodevelopment exhibit deficits in working memory (Seo et al, 1999), delayed alternation tasks (Markowski et al, 2002), and emotional learning (Nishijo et al, 2007). Disturbances in social interaction, an effect that is more pronounced in male animals, is associated with alterations in Ca 2+ /calmodulindependent protein kinase IIα (CaMKIIα) (Nguyen et al, 2013a), a regulator of GABAergic neurotransmission (Guetg et al, 2010;Houston et al, 2009).…”

Learning behavior in rat offspring after in utero and lactational exposure to either TCDD or PCB126

“…In several studies, researchers who examined the effects of TCDD exposure during pregnancy or lactational period on offspring reported that the doses of TCDD used in their study were sufficiently low not to affect dams, but sufficiently high to disrupt offspring's learning behavior, as evaluated using various behavioral tests, such as matching-to-sample learning tasks in monkeys [19], a cued alternation task in rats [20] and a schedule-controlled operant behavior procedure in rats [21]. Therefore, we selected a dose of PCB126 and TCDD that presumably does not affect even the body weight of dams.…”

“…The TEF value is a composite one that is derived, on the basis of a so-called expert assessment, from the relative potency (REP) obtained from various experiments, both in vivo and in vitro. Previous in vivo studies showed that a low TCDD dose that did not affect the dams did disrupt the offspring's learning behavior when the offspring was challenged by various behavioral tests, such as matching-to-sample learning tasks in monkeys [19], a cued alternation task in rats [20] and a schedule-controlled operant behavior procedure in rats [21]. In a cued delayed alternation procedure [20], adult male and female Long-Evans rats, whose dams had been exposed to a single dose of 180 ng/kg of TCDD on gestation day (GD) 15, showed significantly less accurate learning behavior and committed more errors by responding during delay intervals.…”

“…Previous in vivo studies showed that a low TCDD dose that did not affect the dams did disrupt the offspring's learning behavior when the offspring was challenged by various behavioral tests, such as matching-to-sample learning tasks in monkeys [19], a cued alternation task in rats [20] and a schedule-controlled operant behavior procedure in rats [21]. In a cued delayed alternation procedure [20], adult male and female Long-Evans rats, whose dams had been exposed to a single dose of 180 ng/kg of TCDD on gestation day (GD) 15, showed significantly less accurate learning behavior and committed more errors by responding during delay intervals. The results of this study suggested that TCDD interfered with the development of attention processes, impaired response inhibition and/or promoted response inhibition despite the presence of cues, indicating changes in reinforcement contingencies.…”

2,3,7,8-Tetrachlorodibenzo-p-dioxin in maternal breast milk and newborn head circumference

“…Recently, perinatal exposure to TCDD at low doses has been suggested to affect neurodevelopment, and to induce neuro-behavioral alteration in the offspring of rats (Seo et al, 1999;Markowski et al, 2002).…”