Abstract # 43:

Scheduled for Thursday, June 18, 2015 03:30 PM-03:45 PM: (Cascade E) Oral Presentation


J. Cavanaugh, C. M. Rose and J. A. French
University of Nebraska - Omaha, Omaha, NE 68182, USA

Social disruption, isolation, and neglect are a major source of stress and can negatively impact hypothalamic-pituitary-adrenal (HPA) axis functioning in socially monogamous primates; while social support has stress-reducing effects through HPA-axis modulation (Cohen & Wills, 1985). Oxytocin (OXT) plays a critical role in the facilitation of social bonding (Young & Wang, 2004) and may attenuate the bio-behavioral stress response (Smith & Wang, 2012). The goal of the present study was to determine if OXT plays a regulatory role in the social buffering of HPA-axis activity during stress in well-established marmoset (Callithrix jacchus) pairs. Male and female marmosets (n=10) experienced a standardized psychosocial stressor with and without their pair-mate under neuropeptide treatment (Pro8-OXT, Leu8-OXT, OXT antagonist, and saline). Male, but not female, marmosets treated with an OXT antagonist had significantly higher HPA-axis reactivity [F(3,12)=6.88,p=0.006] and total cortisol exposure across the stressor period, relative to vehicle [F(3,12)=9.59,p=0.002]. Female, but not male, marmosets that experienced a stressor with their pair-mate had significantly lower HPA-axis reactivity [F(1,4)=7.07,p=0.05] and total cortisol exposure across the stressor period than females without their pair-mate [F(1,4)=13.87,p=0.02]. These results suggest that endogenous OXT attenuates the stressor-induced rise in cortisol levels in male marmosets, while the presence of a pair-mate buffers HPA-axis activity in females. Thus, the OXT system and social context differentially influence how the HPA-axis responds to stress in male-female marmoset pairs.