Unknown,Transcriptomics,Genomics,Proteomics

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Individual susceptibility to chronic stress is modulated by AMPA receptor function

ABSTRACT: Chronic stress is a key risk factor for a variety of diseases, but the determinants of individual stress susceptibility are still unclear. Using a recently developed paradigm for chronic social stress in mice we identified animals that were resistant or susceptible to the persistent effects of chronic stress exposure. Gene expression analysis in laser-microdissected hippocampal subfields of both groups revealed differentially regulated AMPA receptor subunits, which might affect the susceptibility of an individual to chronic social stress. To test this hypothesis, animals were treated with the AMPA receptor potentiator LY451646 or vehicle during the last 4 weeks of chronic stress exposure. Enhanced AMPA receptor function in chronically stressed animals ameliorated the lasting effects of the chronic stress exposure on physiological, neuroendocrine and behavioural parameters. Our data suggest that differences in AMPA receptor function may underlie individual stress susceptibility and support AMPA receptor potentiators as potential medication in stress-related diseases. Keywords: phenotype, chronic stress, AMPA We have subjected 120 individuals to the chronic social stress procedure, which was recently shown to result in robust effects on neuroendocrine and behavioural parameters (Sterlemann V, 2008). Following the stress procedure all animals were single housed for 7 days. Corticosterone secretion was significantly increased in the chronic stress group compared to controls after one week of single housing. Within the chronic stress group we observed a large variation, where some individuals had recovered from the stress procedure, while others still showed a largely increased corticosterone secretion. After 4 more weeks of single housing, the difference in basal corticosterone secretion between the animals susceptible to chronic stress and unsusceptible or control subjects was still evident. From the group extremes in the chronically stressed animals we selected the 6 most-affected and the 6 most resistant individuals. To investigate the mechanisms underlying the observed differences in individual stress susceptibility between these mice we laser dissected the CA1 and the dentate gyrus region of the hippocampus in the selected mice and performed a gene expression profiling analysis. Pooled amplified RNA samples were then hybridised on Illumina mouse BeadChips (N=4 per group) and detected in the Illumina BeadArray Reader (Illumina, Inc., San Diego, CA).

ORGANISM(S): Mus musculus

SUBMITTER: Karin Ganea

PROVIDER: E-GEOD-11211 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Individual susceptibility to chronic stress is modulated by AMPA receptor function

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