Perinatal exposure to polychlorinated biphenyls alters social behaviors in rats

Abstract

Perinatal exposure to polychlorinated biphenyls (PCBs) leads to significant alterations of neural and hormonal systems. These alterations have been shown to impair motor and sensory development. Less is known about the influence of PCB exposure on developing emotional and motivational systems involved in social interactions and social learning. The present study examined the impact of perinatal PCB exposure (mixture of congeners 47 and 77) on social recognition in juvenile animals, conspecific-directed investigation in adults and on neural and hormonal systems involved in social functions. We used a standard habituation–dishabituation paradigm to evaluate juvenile recognition and a social port paradigm to monitor adult social investigation. Areal measures of the periventricular nucleus (PVN) of the hypothalamus were obtained to provide correlations with related hormone and brain systems. PCB exposed rats were significantly impaired in social recognition as indicated by persistent conspecific-directed exploration by juvenile animals regardless of social experience. As adults, PCB exposure led to a dampening of the isolation-induced enhancement of social investigation. There was not a concomitant alteration of social investigation in pair-housed PCB exposed animals at this stage of development. Interestingly, PVN area was significantly decreased in juvenile animals exposed to PCB during the perinatal period. Shifts in hypothalamic regulation of hormones involved in social behavior and stress could be involved in the behavioral changes observed. Overall, the results suggest that PCB exposure impairs context or experience-dependent modulation of social approach and investigation. These types of social-context deficits are similar to behavioral deficits observed in social disorders such as autism and other pervasive developmental disorders.

Rat pup social motivation: A critical component of early psychological development

“…In another related set of studies we have completed a series of studies examining the influence of perinatal exposure to a toxicant, polychlorinated biphenyl (PCB) on social motivation and social learning (Cromwell et al, 2007; Joulous-Jamshidi, 2010). Using the similar conditioned odor preference test, we uncovered a significant alteration in the expression of maternal cue preference (Cromwell et al, 2007).…”

The effects of prenatal PCBs on adult social behavior in rats

“…BPA also perturbs social recognition in mice (Wolstenholme et al, 2013). Exposure to other EDCs such as atrazine (mice: Belloni et al, 2011), PCBs (rats: Jolous-Jamshidi et al, 2010), and chlorpyrifos (mice: Venerosi et al, 2012) are associated with perturbations of normal social interactions. Polychlorinated biphenyls (PCBs) - including the Aroclor 1221 mixture (A1221) used in the current study – also disrupt sexual behavior in female rats (Chung and Clemens, 1999; Steinberg et al, 2007).…”

Delayed effects of developmental exposure to low levels of the aryl hydrocarbon receptor agonist 3,3′,4,4′,5-pentachlorobiphenyl (PCB126) on adult zebrafish behavior

“…In some cases the effects were still measurable in school-age children even though exposure levels declined substantially after weaning, suggesting that the neurotoxicity associated with prenatal exposure may have long-term implications. These findings are further supported in a number of mammalian studies demonstrating that developmental exposure to dioxins and dioxin-like PCBs resulted in impairment of advanced brain functions such as learning and memory, deficits in socioemotional behavior, and increased anxiety in response to mild stress, occurring at the juvenile and/or adult stages (Hany et al, 1999, Jolous-Jamshidi et al, 2010, Kakeyama et al, 2014, Kakeyama and Tohyama, 2003, Nguyen et al, 2013a, Orito et al, 2007, Piedrafita et al, 2008, Schantz and Widholm, 2001, Zimmer et al, 2009). However, the full potential for later-life neurobehavioral effects that result from early-life low level exposure to dioxin-like compounds is not well understood.…”