Reduced anxiety in postpartum rats requires recent physical interactions with pups, but is independent of suckling and peripheral sources of hormones
Section snippets
Subjects
Subjects were female Long–Evans rats, descended from male and female rats purchased from Harlan Laboratories (Indianapolis, IN), that were born and raised in our colony. After weaning at 21 days of age, subjects were housed in clear polypropylene cages (48 × 28 × 16 cm) with wood shavings for bedding in groups of 2–3 female littermates per cage. Beginning at 75 days old, females' estrous cycles were monitored daily with a vaginal impedance meter (Fine Science Tools, Foster City, CA) and females
Temporal factors influencing anxiety during lactation
In almost all studies demonstrating the anxiolytic effects of lactation in rats, dams have been tested during the early postpartum period. This may have been fortuitous, because we demonstrate here that reduced anxiety is not found throughout all of lactation and is only evident soon after parturition and through the first postpartum week. Some studies reporting no differences between the behavior of lactating and virgin females in the elevated plus-maze did, in fact, test females during the
Acknowledgments
The assistance of Tami Menard and Naffie Ceesay in completing these experiments is greatly appreciated. This research was funded by an intramural research grant for new faculty provided by Michigan State University.
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Lactation is not required for maintaining maternal care and active coping responses in chronically stressed postpartum rats: Interactions between nursing demand and chronic variable stress
2021, Hormones and BehaviorCitation Excerpt :Collectively, these studies suggest a bidirectional relationship between breastfeeding cessation and peripartum depression, which is further mediated by women's expectation to breastfeed (Borra et al., 2015). The postpartum period is associated with enhanced stress resilience (e.g., Leuner and Shors, 2006; Lonstein, 2005; Workman et al., 2016), although whether postpartum stress resilience requires nursing remains unclear. The primary goals of this study were to determine the effects of the absence of nursing and high nursing demand on behavioral and neural responses in a chronic stress model.
Oxytocin receptors in the midbrain dorsal raphe are essential for postpartum maternal social and affective behaviors
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