Trait anxiety, HPA-axis activity and cell adhesion molecules

Abstract

Stress alters physiology and behavior of some individuals, while others are little or not affected. Aim of this thesis was to test whether epigenetically induced levels of trait anxiety predict the stress response of mice in a genetically homogeneous population. Inbred C57BL/6J mice display a remarkably high interindividual variability in their trait anxiety, which predicts the behavioral and neuroendocrine response to acute stress, indicating that extremely different coping strategies can develop in genetically identical individuals. Differences in trait anxiety and stress response seem to be moderated by the function of hippocampal glucocorticoid receptor and expression levels of the neural cell adhesion molecule NCAM. Moreover, the behavioral response to drugs of addiction (cocaine) is higher in mice with high levels of trait anxiety and high stress response than in mice with low levels of trait anxiety and low stress susceptibility.