Neural Mechanisms of Exercise-Induced Stress Resilience In Females

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Presenter(s)

Troy Hubert

Abstract or Description

Inescapable stressors are associated with the onset of stress-related disorders, such as depression and anxiety. Despite the fact that the incidence of stress-related disorders is higher in females than males, there has been less research on the mechanisms underlying stress disorders and stress resilience factors in females. One sex difference in stress resilience seems to be that female rats are more responsive to the stress-buffering effects of exercise than males. Specifically, while six weeks of voluntary exercise can protect male rats from the anxiety- and depression-like behavioral effects of inescapable stress, only 3 weeks of exercise is required to enable similar stress resilience in females. Excessive activation of serotonergic (5-HT) neurons within the dorsal raphe nucleus (DRN) is largely responsible for the anxiogenic and depressive behaviors following inescapable stress. In male rats, exercise enables stress resilience by constraining activation of these stress-promoting DRN 5-HT neurons. However, whether a similar mechanism underlies the rapid stress resilience produced by 3 weeks of exercise in females is unknown. The goal of the present study is to determine if both 3 and 6 weeks of voluntary exercise constrains activation of DRN 5-HT neurons during exposure to inescapable stress in females. Double-label immunohistochemistry is being used to label DRN 5-HT neurons and mark their activity with the neural activation marker, cFos. Data collection is ongoing. Results of this study have to potential to reveal novel, fast-acting, and potentially sex-specific targets of stress resilience.