Abstract # 143:

Scheduled for Friday, August 19, 2005 04:00 PM-04:15 PM: Session 13 (Parliament Room) Oral Presentation


ACUTE EFFECTS OF PSYCHOSOCIAL STRESSORS ON THE MOTHER AND FETUS IN PIGTAILED MACAQUES (Macaca nemestrina)

M. S. Novak1, G. P. Sackett2 and C. Kenney1
1Laboratory of Comparative Ethology - NICHD, NIH Animal Center, Poolesville, MD 20837, USA, 2Infant Primate Research Laboratory and Washington National Primate Research Center, Seattle, Washington.
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     Prenatal stress literature links prenatal events to improvements, decrements, and no changes in postnatal development. Stress is subjective and difficult to operationalize. In addition, acute effects of a stressor are rarely measured, weakening any assumption that a stressor has occurred. The time course of acute interactions may inform us about the likelihood of specific mechanisms. In this study, acute fetal cardiovascular responses to prenatal maternal challenges were studied. Changes were measured with chronic catheters implanted on gestational day 120 and maintained through the end of pregnancy (~170 days). Four pregnant pigtailed macaques were challenged with three psychosocial events, receiving food treats, observing other animals receive food treats, and anticipating but not experiencing capture. Fetal cardiovascular variables were collected continuously for five minutes prior to and during a challenge episode. Changes were determined using the mean of the previous second plus or minus the interquartile range of the previous 20 seconds, similar to procedures for studying acute changes in heart rate in human fetuses reported by Lecanuet and Jacquet (2002). Using this method, changes during baseline conditions were rare (5.5%). The fetal cardiovascular system responded often (75%; P < 0.05, binomial sign test) and rapidly (Range = 1-108 seconds) to maternal challenges. The magnitude and direction of response depended on the individual and the nature of the challenge episode and may shed light on proposed mechanisms of prenatal stress. NCRR-RR00166CHDD/NICHD-HD02274