Abstract # 1913 Event # 111:

Scheduled for Friday, August 18, 2006 10:30 AM-10:45 AM: Session 10 (Regency East #2) Oral Presentation


Social support modulates the behavioral and hypothalamic-pituitary-adrenal axis response to maternal separation in infant rhesus macaques (Macaca mulatta)

M. L. Schwandt1, S. J. Suomi2 and J. D. Higley1
1NIH/NIAAA, Laboratory of Clinical and Translational Studies, PO Box 529, Poolesville, MD 20837, USA, 2NIH/NICHD, Laboratory of Comparative Ethology
line
     Studies of humans and nonhuman primates suggest that the presence of social support during times of stress alters both the behavioral and physiological response to stress. In this study we investigated the effect of social support on the behavioral and hypothalamic-pituitary-adrenal axis response to maternal separation in infant rhesus macaques. During separation testing, infants with social support (SS infants, n = 27) remained in their respective social groups, comprised of other adult females, adult males, and their offspring, while the mother was removed. Infants without social support (NSS infants, n = 27) were removed from the social group along with their mothers and housed in single cages separate from their mothers. Each infant subject underwent four consecutive four-day long separations, with each separation followed by three days of reunion with their mothers. NSS infants showed increased signs of behavioral agitation during both the acute (day 1) and chronic (days 2-4) stages of separation, with increased levels of stereotypic behavior, locomotion, and vocalizations (ANOVA, all p < 0.01). During the acute stage, NSS infants showed higher ACTH and cortisol levels than SS infants (ANOVA, both p < 0.05). However, during the chronic stage, NSS infants showed significantly lower ACTH levels (ANOVA, p < 0.0001). These data are consistent with the notion that the presence of social support modulates the response to maternal separation stress.