Neuroscience 2005 Abstract
| Presentation Number: | 446.8 |
|---|---|
| Abstract Title: | Psychosocial stress-induced neurochemical changes in hippocampus and prefrontal cortex in rats. |
| Authors: |
Steiniger-Brach, B.*1
; Ahnaou, A.1
; Vaarties, K.1
; Drinkenburg, W. H. I.1
1CNS Psychiatry 2: Biomonitoring, Johnson and Johnson PRD, Beerse, Belgium |
| Primary Theme and Topics |
Disorders of the Nervous System - Cognitive, Emotional and Behavioral State Disorders -- Affective disorders: Animal models |
| Secondary Theme and Topics | Disorders of the Nervous System<br />- Behavioral Pharmacology<br />-- Monoamines and behavior |
| Session: |
446. Animal Models of Depression: Stress and Depression I Poster |
| Presentation Time: | Monday, November 14, 2005 11:00 AM-12:00 PM |
| Location: | Washington Convention Center - Hall A-C, Board # UU16 |
| Keywords: | DEPRESSION, MONOAMINE, MICRODIALYSIS, ANIMAL MODEL |
Stress, especially if psychological and uncontrollable, favors the development and aggravation of depression. In rodents repeated social defeat could be equivalent to loss of control and has been shown to induce behavioral and physiological changes that resemble some symptoms of depression. Consequently, repeated social defeat has been proposed as a model for depression and the study of underlying mechanisms and changes induced could yield inside into the etiology of human depression. In the present study we used in vivo microdialysis in subordinate rats to investigate extracellular levels of monoamines in prefrontal cortex and hippocampus under the influence of psychosocial stress.
Rats followed a resident-intruder protocol for four consecutive days, during which physiological parameters were monitored (see SfN poster Ahnaou et al 2005). On day five, rats had visual, acoustic and olfactory, but no physical contact to dominant rats. This situation dissociates physical defeat stress from psychosocial stress. On this day, dopamine and noradrenaline in the prefrontal cortex and serotonin in the hippocampus were measured. To prevent any confounding effects of placing rats into a new environment (cage of dominant rats), control rats were placed in a novel cage on five consecutive days.
Subordinate rats had lower baseline serotonin and higher baseline dopamine levels as compared to controls. No differences in baseline noradrenaline levels were found. During psychosocial stress serotonin, dopamine and noradrenaline levels were elevated. However, also control conditions elevated noradrenaline, but not dopamine or serotonin levels.
The dynamic changes seen specifically in the serotonergic and dopaminergic systems before and after psychosocial stress, indicate an involvement in mechanisms underlying changes induced by repeated social defeat. Especially, the reduced baseline serotonin levels are in line with data from depressed patients and further validates the concept of repeated social defeat as a rodent model for aspects of depression.
Rats followed a resident-intruder protocol for four consecutive days, during which physiological parameters were monitored (see SfN poster Ahnaou et al 2005). On day five, rats had visual, acoustic and olfactory, but no physical contact to dominant rats. This situation dissociates physical defeat stress from psychosocial stress. On this day, dopamine and noradrenaline in the prefrontal cortex and serotonin in the hippocampus were measured. To prevent any confounding effects of placing rats into a new environment (cage of dominant rats), control rats were placed in a novel cage on five consecutive days.
Subordinate rats had lower baseline serotonin and higher baseline dopamine levels as compared to controls. No differences in baseline noradrenaline levels were found. During psychosocial stress serotonin, dopamine and noradrenaline levels were elevated. However, also control conditions elevated noradrenaline, but not dopamine or serotonin levels.
The dynamic changes seen specifically in the serotonergic and dopaminergic systems before and after psychosocial stress, indicate an involvement in mechanisms underlying changes induced by repeated social defeat. Especially, the reduced baseline serotonin levels are in line with data from depressed patients and further validates the concept of repeated social defeat as a rodent model for aspects of depression.
Sample Citation:
[Authors]. [Abstract Title]. Program No. XXX.XX. 2005 Neuroscience Meeting Planner. Washington, DC: Society for Neuroscience, 2005. Online.
Copyright © 2005-2026 Society for Neuroscience; all rights reserved. Permission to republish any abstract or part of any abstract in any form must be obtained in writing by SfN office prior to publication.
