Friday, October 12, 2012: 4:20 PM
Hall 4E/F (WSCC)
John Preslik
,
Psychology / Integrative Biology, University of California, Berkeley, Berkeley, CA
Samuel Sakhai
,
Psychology, University of California, Berkeley, Berkeley, CA
Darlene Francis, PhD
,
Public Health, University of California, Berkeley, Berkeley, CA
Variations in maternal care are associated with the development of individual differences in behavioral and hypothalamic-pituitary-adrenal responses to stress in the rat. Environmental stressors can influence maternal care and hidden variables can be problematic for research in behavioral science. When executing experiments involving animal models, the animal’s environment can have a dramatic influence on the results. We demonstrated how variations in postnatal environments, in the form of bedding material, could lead to significant differences in maternal behavior and significantly alter the concentration of glucocorticoid receptors in hippocampus of the offspring resulting in abnormal anxiety like behavior that persisted throughout adulthood.
Fifteen female long-evans rats were mated and allowed to raise their offspring on one of two types of bedding material Tek-Fresh or Purlite. The activities of postnatal dams were observed three times a day for one-hour intervals and the quality of maternal care administered was determined. Dams' were then categorized as providing High, Mid and Low levels of maternal care. All male offspring were tested for anxiety after weaning using open field, light dark box and plus maze assessments. The male offspring were then euthanized and their brains were collected. Concentrations of glucocorticord receptors contained in the hippocampus of these offspring were measured using a western blot.
The results have shown a significant difference in anxiety like behavior between pups raised on Tek-Fresh and those raised on Purlite with a significantly lower concentration of GR receptors found in the brains of the more anxious offspring.
