Chronic corticosterone increases Δfosb and crfr1 immunoreactivity in brain regions that modulate aversive conditioning.

CHRONIC CORTICOSTERONE INCREASES ΔFOSB AND CRFR1 IMMUNOREACTIVITY IN BRAIN REGIONS THAT MODULATE AVERSIVE CONDITIONING.
Behav Brain Res. 2018 Aug 14;:
Authors: Scalize Hirata RY, Dos Santos TB, de Andrade JS, Le Sueur Maluf L, Antunes HKM, Britto LRG, Céspedes IC, de Barros Viana M
Abstract
Previous studies showed that chronic treatment with corticosterone facilitates elevated T-maze (ETM) inhibitory avoidance and a step-down avoidance task, responses that have been used to investigate aversive conditioning and memory processes. On the other hand, chronic corticosterone does not alter ETM escape from the open arms. The purpose of the present study was to further investigate the effects of chronic corticosterone treatment (200 mg pellets, 21-day release) in an animal model of anxiety that does not involve aversive conditioning: the light/dark transition model. We also investigated the pattern of ΔFosB immunoreactivity (ΔFosB-ir) in different brain regions. To examine how treatment with chronic corticosterone interferes with CRFR1 expression we measured CRFR1 in the same brain structures that exhibited increased ΔFosB-ir. Results showed that chronic treatment with corticosterone did not alter behavioral measurements performed in the light/dark transition model. On the other hand, ΔFosB-ir was increased in several structures that modulate aversive conditioning: the cingulate cortex, the ventro and dorsolateral septum, the amygda...

Source: Behavioural Brain Research - August 14, 2018 Category: Neurology Authors: Scalize Hirata RY, Dos Santos TB, de Andrade JS, Le Sueur Maluf L, Antunes HKM, Britto LRG, Céspedes IC, de Barros Viana M Tags: Behav Brain Res Source Type: research