Abstract
Variations in serotonin transporter (5-HTT) expression have been associated with altered sensitivity to stress. Since controllability is known to alter the impact of a stressor through differential activation of the medial prefrontal cortex (mPFC) and dorsal raphe nucleus (DRN), and that these regions are functionally affected by genetic 5-HTT down-regulation, we hypothesized that 5-HTT expression modulates the effect of controllability on stressor impact and coping. Here, we investigated the effects of a signaled stress controllability task or a yoked uncontrollable stressor on behavioral responding and mPFC and DRN activation. 5-HTT-/- rats proved better capable of acquiring the active avoidance task than 5-HTT+/+ animals. Controllability determined DRN activation in 5-HTT+/+, but not 5-HTT-/-, rats, whereas controllability-related activation of the mPFC was independent of genotype. These findings suggest that serotonergic activation in the DRN is involved in stress coping in a 5-HTT expression dependent manner, whereas mPFC activation seems to be implicated in control over stress independently of 5-HTT expression. We speculate that alterations in serotonergic feedback in the DRN might be a potential mechanism driving this differential stress coping.
Original language | English (US) |
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Pages (from-to) | 1143-1150 |
Number of pages | 8 |
Journal | ACS Chemical Neuroscience |
Volume | 6 |
Issue number | 7 |
DOIs | |
State | Published - Jul 15 2015 |
Keywords
- Serotonin
- avoidance
- controllability
- dorsal raphe nucleus
- serotonin transporter
- stress
ASJC Scopus subject areas
- Biochemistry
- Physiology
- Cognitive Neuroscience
- Cell Biology