title: Corticosterone attenuates conditioned fear responses and potentiates the expression of GABA-A receptor alpha-2 subunits in the brain structures of rats selected for high anxiety.
abstract: The aim of the experiment was to assess the effects of an acutely administered corticosterone on the expression of GABA-A receptor alpha-2 subunits in the brain structures of high (HR) and low (LR) anxiety rats (divided according to their conditioned fear-induced freezing response) subjected to a second conditioned fear session (1 week after fear conditioning). We found that corticosterone (20 mg/kg, sc) given to rats prior to the second conditioned fear session significantly enhanced a decrease in fear expression in the HR group. The behavioural effect of fear was accompanied by the increased expression of alpha-2 subunits in the basolateral amygdala (BLA) and the dentate gyrus of the hippocampus (DG) of the HR group. Corticosterone potentiated the effect of fear on alpha-2 subunit expression in the BLA, DG, the cingulate cortex area 1 and the secondary motor cortex (areas Cg1 and M2). The current study provides insight into the mechanisms that may be responsible for the beneficial effects of glucocorticoids in the therapy of some anxiety disorders.
authors: Department of Experimental and Clinical Pharmacology, Medical University of Warsaw, 26/28 Krakowskie Przedmieście Street, 00-927 Warsaw, Poland. awislow@yahoo.com
authors: A
authors: A
authors: Wisłowska-Stanek
authors: M
authors: M
authors: Lehner
authors: A
authors: A
authors: Skórzewska
authors: P
authors: P
authors: Maciejak
authors: J
authors: J
authors: Szyndler
authors: D
authors: D
authors: Turzyńska
authors: A
authors: A
authors: Sobolewska
authors: A
authors: A
authors: Płaźnik
mesh_terms: D000679:Amygdala / Q000187:drug effects / Q000378:metabolism*; D000818:Animals; D001007:Anxiety / Q000188:drug therapy* / Q000378:metabolism; D003213:Conditioning, Psychological / Q000187:drug effects; D003345:Corticosterone / Q000494:pharmacology / Q000627:therapeutic use*; D018891:Dentate Gyrus / Q000187:drug effects / Q000378:metabolism*; D004195:Disease Models, Animal; D005239:Fear / Q000187:drug effects; D006179:Gyrus Cinguli / Q000187:drug effects / Q000378:metabolism*; D046353:Immobility Response, Tonic / Q000187:drug effects; D008297:Male; D009044:Motor Cortex / Q000187:drug effects / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D011963:Receptors, GABA-A / Q000096:biosynthesis*; D015854:Up-Regulation / Q000187:drug effects
chemical_list: C520011:Gabra2 protein, rat; D011963:Receptors, GABA-A; D003345:Corticosterone