In the study led by Darlene Francis, PhD, a postdoctoral fellow at Emory University's Yerkes National Primate Research Center, and Thomas Insel, MD, former director of the CBN and current director of the National Institute of Mental Health, the scientists selected two in-bred mouse strains known to differ in their stress reactivity (high versus low) and cognitive performance. All the mice within each in-bred strain were identical.
To gauge the influence of different uterine and early-life environments on development, the scientists transferred embryos from recently mated low-stress (B6) female mice to female surrogates from the strain that displayed high-stress reactive profiles (BALBs). For comparison purposes, they also transferred embryos to surrogate females within the same strain.
At birth, all mice were cross-fostered again and reared by either a low-stress B6 mother or a high-stress BALB mother. When all of the offspring reached adulthood at three months of age, the researchers compared their stress reactions and cognitive performance. The low-stress B6 mice that were transferred as embryos to and also later reared by surrogate BALB females demonstrated an increase in stress-reactive behaviors. These mice were less likely to explore new environments than their genetically identical counterparts that were carried and reared by low-stress mothers. The low-stress B6 mice reared by surrogate BALB females also performed more poorly on cogniti
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Contact: Holly Korschun
hkorsch@emory.edu
404-727-3990
Emory University Health Sciences Center
12-May-2003