A role for glucocorticoids in the long-term establishment of a social hierarchy

Abstract

Stress can affect the establishment and maintenance of social hierarchies. In the present study, we investigated the role of increasing corticosterone levels before or just after a first social encounter between two rats of a dyad in the establishment and the long-term maintenance of a social hierarchy. We show that pre-social encounter corticosterone treatment does not affect the outcome of the hierarchy during a first encounter, but induces a long-term memory for the hierarchy when the corticosterone-injected rat becomes dominant during the encounter, but not when it becomes subordinate. Post-social encounter corticosterone leads to a long-term maintenance of the hierarchy only when the subordinate rat of the dyad is injected with corticosterone. This corticosterone effect mimics previously reported actions of stress on the same model and, hence, implicates glucocorticoids in the consolidation of the memory for a recently established hierarchy.

Stress pulls us apart: Anxiety leads to differences in competitive confidence under stress

“…These remarkable findings suggest that glucocorticoids impinge a differential responsiveness in brain function and behavior in individuals that differ in trait anxiety, and fit with the idea that enhanced glucocorticoid levels would facilitate behavioral responses according to existing predispositions. This idea is in line with rodent studies indicating that acute increases in the stress hormone corticosterone exacerbate context-dependent status, increasing agonistic responses in dominant individuals while submissive responses in subordination [see Timmer and Sandi (2010) for a discussion; note, though, that the link between context and anxiety in those examples remains to be established]. In addition, the implication of cortisol in the performance in the economic game is in line with formerly reported rapid effects of glucocorticoids in behavioral coping (Sandi et al, 1996) and social interactions (Mikics et al, 2004).…”

Maternal exposure to environmental enrichment before and during gestation influences behaviour of rat offspring in a sex-specific manner

“…The colony was habituated to the arena for 10 min, at the end of which a bottle containing pear juice (a beverage very palatable to rats) was inserted on one side of the arena for 30 min. The juice represents a source of stimulation for the agonistic interactions we wanted to record [35]. During the pear juice exposure, animals established low intensity conflict interactions for access to drink and we determined a dominance hierarchy based on agonistic interactions in a group context competition [36] for a palatable drink.…”

Increase in Alzheimer's related markers preceeds memory disturbances: Studies in vasopressin-deficient Brattleboro rat

“…To avoid possible confounding effect of social contact with other rats (e.g. hierarchy [61]) all experiments were performed on single-housed animals (approx. 1 week isolation).…”