Abstract # 2622 Event # 179:

Scheduled for Monday, September 21, 2009 09:45 AM-09:55 AM: Session 16 (Mission Bay Ballroom AB) Oral Presentation


M. L. Power1,2, L. E. Williams3, S. V. Gibson4, J. Schulkin2, J. Helfers5 and E. P. Zorrilla5
1Smithsonian National Zoological Park, Nutrition Laboratory, Conservation and Ecology Center, Washington , DC 20008, USA, 2American College of Obstetricians and Gynecologists, 3University of Texas M.D. Anderson Cancer Research Center, 4University of South Alabama, 5The Scripps Research Institute

The anthropoid primate placenta appears to be unique in producing corticotropin-releasing hormone (CRH). There are at least two patterns of maternal circulating CRH among anthropoids. Monkeys examined to date (Papio and Callithrix) have an early-to-mid gestational peak of circulating CRH, followed by a steady decline to a plateau level, with a possible rise near parturition. In contrast, humans and great apes have an exponential rise in circulating CRH peaking at parturition. We examined maternal circulating CRH in squirrel (Saimiri boliviensis) and owl (Aotus nancymaae) monkeys. Blood samples were collected monthly on 14 squirrel and 10 owl monkeys during pregnancy. CRH immunoreactivity was measured from extracted serum by solid-phase RIA. Both squirrel and owl monkeys displayed a mid-gestational peak in circulating CRH: days 50-75 of the 150 day gestation for squirrel monkeys [mean CRH=2786±282 pg/ml] and days 60-80 of the 135 day gestation for owl monkeys [mean CRH=9871±974 pg/ml]. In squirrel monkeys circulating CRH declined to 38% of mean peak value by two weeks from parturition and then appeared to increase. In owl monkeys circulating CRH appeared to plateau with no subsequent significant decline approaching parturition. This study provides additional evidence for an ancestral mid-gestational peak of maternal circulating CRH in anthropoids which has been lost in the hominoid lineage. Supported by PHS grants P40 RR01254, 5R24 RR020052 and P01 DK26741.