Premium
Increased CRF 2 expression in the dorsal raphe is associated with passive behavioral responses to stress
Author(s) -
Bangasser Debra Ann,
Wood Susan K.,
Howard Owen,
Carr Gregory V.,
Bhatnagar Seema,
Lucki Irwin,
Valentino Rita J.
Publication year - 2009
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.23.1_supplement.591.3
Subject(s) - behavioural despair test , antidepressant , endocrinology , medicine , serotonin , dorsal raphe nucleus , chronic stress , corticotropin releasing hormone , 5 ht receptor , psychology , receptor , neuroscience , serotonergic , hippocampus
The dorsal raphe (DR)‐serotonin (5‐HT) system is implicated in stress‐related psychiatric disorders, like depression. Corticotropin‐releasing factor (CRF) modulates activity of this system during stress via activation of two receptors: CRF 1 and CRF 2 . CRF 1 mediated inhibition of the DR‐5‐HT system facilitates active behavioral responses to stress. In contrast, CRF 2 can excite the DR‐5‐HT system, an effect that may mediate passive responses to stress. Here we used genetic, behavioral, and pharmacological models to determine whether changes in CRF 2 expression in the DR are associated with passive behavior. Western Blots were first used to demonstrate that rats of the behaviorally passive Wistar Kyoto strain express more CRF 2 protein in the DR than Sprague‐Dawley (SD) rats. In the second experiment, SD rats exposed to chronic social defeat, which results in passive behavior on the forced swim test (FST), expressed more CRF 2 in the DR than their unstressed counterparts. Finally, chronic antidepressant treatment that decreases passive responses on the FST resulted in fewer CRF 2 in the DR. None of these models altered DR expression of CRF 1 . These studies suggest that greater CRF 2 expression in the DR correlates with a passive behavioral strategy. Because passive responses to stress are associated with increased vulnerability to depression in humans, CRF 2 may be a novel target for treating stress‐related disorders.