Asymmetrical expression of BDNF and NTRK3 genes in frontoparietal cortex of stress-resilient rats in an animal model of depression

Sara Farhang, Jaleh Barar, Ali Fakhari, Mehran Mesgariabbasi, Sajjad Khani, Yadollah Omidi, Alireza Farnam

Research output: Contribution to journalArticleAcademicpeer-review

21 Citations (Scopus)

Abstract

The current study is based on the "approach-withdrawal" theory of emotional regulation and lateralization of brain function in rodents, which has little been studied. The aim was to indentify asymmetry in hemispheric genes expression during depression. Depressive-like symptoms were induced in rats using chronic mild stress protocol. The sucrose consumption test was performed to identify the anhedonic and stress-resilient rats. After decapitation, RNA was extracted from frontotemporal cortex of both hemispheres of anhedonic and stress-resilient rats. The pattern of gene expression in these samples was compared with controls by real-time polymerase chain reaction. A linear mixed model analysis of variance was fitted to the data to estimate the effect of rat line. From the total of 30 rats in the experimental group, five rats were identified to be anhedonic and five were stress-resilient, according to the result of sucrose-consumption test. BDNF and NTRK-3 were expressed at significantly lower levels in the right hemisphere of anhedonic rats compared with stress-resilient rats. No significant difference was found between left hemispheres. Hemispheric asymmetry in the level of gene expression was only observed for the BDNF gene in stress-resilient rats, upregulated in right hemisphere compared with the left. Expression of NTRK3, HTR2A, COMT, and SERT was not lateralized. There was no significant asymmetry between hemispheres of anhedonic rats. This study supports the evidence for the role of genes responsible for neural plasticity in pathophysiology of depression, emphasizing probable hemispheric asymmetry at level of gene expression.

Original languageEnglish
Pages (from-to)387-393
Number of pages7
JournalSynapse
Volume68
Issue number9
DOIs
Publication statusPublished - Sep-2014
Externally publishedYes

Keywords

  • Anhedonia
  • Animals
  • Brain-Derived Neurotrophic Factor
  • Catechol O-Methyltransferase
  • Depressive Disorder
  • Dietary Sucrose
  • Disease Models, Animal
  • Frontal Lobe
  • Functional Laterality
  • Gene Expression
  • Linear Models
  • Male
  • RNA-Binding Proteins
  • Random Allocation
  • Rats, Wistar
  • Real-Time Polymerase Chain Reaction
  • Receptor, Serotonin, 5-HT2A
  • Receptor, trkC
  • Resilience, Psychological
  • Stress, Psychological
  • Temporal Lobe
  • Journal Article
  • Research Support, Non-U.S. Gov't

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