Behavioural and neurochemical effects induced by chronic mild stress applied to two different rat strains

Autor: Spyros Daskas, Stathis Bekris, Katerina Antoniou, Zeta Papadopoulou-Daifoti
Rok vydání: 2005
Předmět:
Male
Imipramine
Sucrose
Time Factors
Dopamine
Hippocampus
Striatum
Antidepressive Agents
Tricyclic
Hippocampal formation
Brain Chemistry/drug effects/*physiology
Serotonin/metabolism
Rats
Sprague-Dawley
Eating
Behavioral Neuroscience
Behavior
Animal/drug effects/*physiology
Behavior
Animal
Dopaminergic
Brain
Hydroxyindoleacetic Acid
Antidepressive Agents
Tricyclic/therapeutic use
Hydroxyindoleacetic Acid/metabolism
medicine.drug
Serotonin
medicine.medical_specialty
Food Preferences/drug effects
Brain/anatomy & histology/drug effects/metabolism/physiopathology
Biology
Serotonergic
3
4-Dihydroxyphenylacetic Acid/metabolism
Food Preferences
Neurochemical
Species Specificity
Stress
Physiological
Internal medicine
medicine
Animals
Rats
Wistar
Eating/drug effects/physiology
Brain Chemistry
Analysis of Variance
Stress
Physiological/drug therapy/*metabolism/physiopathology
Body Weight
Imipramine/therapeutic use
Homovanillic Acid
Homovanillic Acid/metabolism
Rats
Dopamine/metabolism
Endocrinology
Body Weight/physiology
Chronic Disease
3
4-Dihydroxyphenylacetic Acid
Zdroj: Behavioural Brain Research. 161:45-59
ISSN: 0166-4328
DOI: 10.1016/j.bbr.2005.01.005
Popis: Chronic mild stress (CMS) has been reported to induce an anhedonic-like state in rats that resembles some of the symptoms of endogenous depression in humans. In the present study, CMS-induced behavioural responses along with neurochemical alterations in dopaminergic and serotonergic function in prefrontal cortex, striatum, hypothalamus and hippocampus were examined following treatment with imipramine in Wistar and Sprague-Dawley rats. The CMS procedure lasted 7 weeks in total. Once per week, a 1-h preference test for 1% sucrose solution was conducted. Treatment with imipramine (10mg/kg i.p., once daily) commenced after experimental week 3. CMS induced significant reductions in absolute and relative sucrose intake and sucrose preference in both rat strains but their temporal pattern was different especially during the weeks 0-3. These effects were reversed by IMI. An increase in the dopaminergic and a decrease in the serotonergic activity were observed in the prefrontal cortex in both rat strains following CMS. A decrease in the striatal dopaminergic activity and an increased hippocampal serotonergic activity were also seen in both rat strains following CMS. In Wistar rats, dopaminergic and serotonergic activities were enhanced in the hypothalamus whereas in Sprague-Dawley rats no such stress-induced changes were observed. Notably, the clear decrease in sucrose consumption observed in stressed Wistar rats could be directly associated with a respective increase in the dopaminergic hypothalamic activity. Chronic treatment with imipramine normalized all neurochemical alterations induced by CMS. Our results suggest that a specific and regionally differentiated serotonin-dopamine interaction is directly related to the observed stress-induced anhedonia. Behav Brain Res
Databáze: OpenAIRE
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