Abstract # 69:

Scheduled for Friday, June 18, 2010 03:45 PM-03:55 PM: Session 15 (Medallion Ballroom A) Oral Presentation


RH5-HTTLPR AND PEER REARING COMPROMISE SOCIAL BUFFERING OF AROUSAL AND FEAR IN JUVENILE RHESUS MACAQUES (MACACA MULATTA)

K. N. Herman1,2, S. M. McLaughlin3, A. Cummins4, D. Delaney4, K. Vaughan4, P. Noble4, S. J. Suomi1, J. T. Winslow4 and E. E. Nelson3
1Laboratory for Comparative Ethology, NIH Animal Center, Poolesville, MD 20842, USA, 2Department of Human Development University of Maryland College Park, 3Mood and Anxiety Disorders Program, National Institute of Mental Health, 4Primate Core Facility, National Institute of Mental Health
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One advantage of social relationships is faster recovery from stressful experiences when a familiar partner is present, a concept known as ‘social buffering.’ We have described (Winslow et al.,  2003) social buffering deficits in peer-reared but not maternally-reared rhesus macaques. Little is known about the impact of genetic risk factors on social buffering. We examined how the serotonin transporter gene promoter polymorphism (rh5-HTTLPR) and peer rearing influence social buffering of stress behaviors. Subjects were reared in social groups with mothers and peers (MPR), or only peers (PR). Subjects were exposed to a novel cage for 20-minutes with and without their home cage partner on separate days. Repeated-measures ANCOVAs controlling for baseline cortisol with condition as the within-subjects factor, and rh5-HTTLPR and rearing as between-subjects factors revealed a Condition X Rearing interaction on arousal [F(1,25)=11.26, P<0.01, partial η2=0.31] and a Condition X Genotype interaction on fear [F(1,25)=3.99, P=0.05, partial η2=0.14]. During the social condition, PR subjects display higher levels of arousal than MPR subjects [P<0.05], and l/l subjects exhibited higher levels of fear than l/s or s/s subjects [P<0.05]. Additionally, more affiliation was noted in MPR than PR subjects [F(1,25)=11.88, P<0.001, partial η2=0.15] and in l/l compared to l/s or s/s subjects [F(1,25)=4.33, P=0.05, partial η2=0.15]. Thus, in addition to early adversity, genetic risk factors contribute to poor social buffering of arousal and fear behaviors.