Repeated traumatic events induce long-lasting behavioral changes that may mold an individual’s cognitive, emotional, and social response to his/her environment. In animal models, rodents subjected to repeated aggression develop enduring social aversion and increased anxiety. The stress response results in glucocorticoid release and activation of the ascending dopamine system. To study this system, the authors bred mice with selective inactivation of the gene encoding the glucocorticoid receptor along the dopamine pathway, and exposed them to repeated aggressions. Glucocorticoid receptors in dopaminoceptive but not dopamine-releasing neurons specifically promoted social aversion. However, anxiety and fear memories remained unaffected. Acute inhibition of the activity of dopamine-releasing neurons fully restored social interaction in socially defeated wild-type mice. The authors suggest that there is a glucocorticoid receptor-dependent neuronal dichotomy for the regulation of emotional and social behaviors, and suggest that the glucocorticoid receptor may be a link between stress resiliency and dopaminergic activity (tone).
Barik J, Marti F, Morel C, Fernandez SP, Lanteri C, Godeheu G, Tassin JP, Mombereau C, Faure P, Tronche F: Chronic stress triggers social aversion via glucocorticoid receptor in dopaminoceptive neurons. Science 339 (6117): 332-335 (2013).