Cocaine abuse in women is correlated with a high incidence of child neglect and abuse. Additionally, young children prenatally exposed to cocaine have been reported to exhibit early signs of neurobehavioral stress including excessive and high-pitched crying, increased state lability, decreased response to caregivers, stress-related behavioral differences, and poor social behavior in later life. Animal models can more directly assess the neurobiological mechanisms and behavioral responses of drug-treated dams and their drug exposed offspring than human studies, though both are important and can inform one another. Studies have shown that prenatal cocaine exposure alters various cognitive and social behaviors in rats, but less is known about what this exposure does to very early brain development and behavior 'of these pups that may alter maternal behavior even by non drug-treated dams. Using a rat model of cocaine-induced maternal neglect, it was recently found that chronic gestational cocaine (CC) treatment during pregnancy decreased pupdirected maternal behavior (MB) towards their own and non-exposed pups, but data indicated, that mothers from both drug-treated and control groups exhibited delayed or less MB towards cocaine-exposed pups during the early postpartum period. Rodent mothers attend to specific stimuli of pups in caring for them, such as cries, body temperature, nursing elicitation by pups, and olfactory stimuli. Thus, these recent studies suggest that specific characteristics of CC exposed pups may elicit differential care from all post-partum dams. Human mothers using cocaine have been shown to perceive baby cries as less urgent than non-drug using mothers, suggesting that cocaine may also alter the ability of the mother to attend to specific stimuli from their babies. Together these data implicate that cocaine-induced changes in both mother and offspring influence quality of maternal care, although little is understood about the mechanisms underlying these effects. Oxytocin (OT), a neurohormone particularly important for normal maternal, affiliative, and stress response behaviors in non-human animals, has been found to be reduced in CC treated rat dams who display disruptions in early maternal behavior and in offspring who are less social. Interestingly, in a recent human study, women with a history of cocaine abuse had lower plasma levels of oxytocin than mothers with no drug history, were less likely to pick up their babies at home, and had a different endocrine stress response pattern. The proposed studies are designed to determine (a.) if cocaine-exposed (CC) pups exhibit aberrations in behavioral, physiological, neurological, or endocrine characteristics that could influence elicitation of care in the early postnatal period;(b.) how gestational cocaine (CC) or control treatments (untreated-UN, saline treated-CS) in rat dams influence the dam's response to different infant characteristics or behavior;and (c.) if there are differences in physiological, early genetic, endocrine, or neurostructural mechanisms underlying behavioral changes in offspring and/or dams during the early postpartum period that may be disrupting mother-infant interactions when maternal care is so vital.
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