کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
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6228841 | 1276575 | 2008 | 10 صفحه PDF | دانلود رایگان |

BackgroundThe therapeutic value of corticosteroids in the aftermath of traumatic experience has been questioned. We used an animal model of posttraumatic stress disorder (PTSD) to assess long-term behavioral effects of a single administration of various doses of corticosterone (CORT), administered immediately after exposure to psychogenic stress.MethodsAnimals were exposed to predator scent stress and treated 1 hour later with various doses of CORT or saline. The outcome measures included behavior in an elevated plus-maze (EPM) and acoustic startle response (ASR) 30 days after the initial exposure and freezing behavior upon exposure to a trauma-related cue on day 31. Pre-set cut-off behavioral criteria (CBC) classified exposed animals according to behavioral responses in EPM and ASR paradigms as those with “extreme behavioral response,” “minimal behavioral response,” or “intermediate response.” Non-spatial memory task and 24-hour locomotor activity were assessed immediately after injection with CORT or vehicle.ResultsEarly treatment with high-dose CORT reduced the prevalence of PTSD-like behavioral responses relative to saline-control treatment. Cue-induced freezing was significantly lower in the high-dose CORT-treated group. Lower doses of CORT significantly increased anxiety-like behavior, mean startle amplitude, and prevalence of PTSD-like behavioral disruptions, compared with saline-control treatment. The attenuated cue-responsiveness and impaired performance on a memory task imply that one key factor in this effect is the disruption of traumatic memory consolidation.ConclusionsSingle treatment with high-dose CORT immediately after stressful exposure reduces the prevalence rate of extreme behavioral disruption 30 days later. Corticosterone might disrupt the consolidation of aversive or fearful memories.
Journal: Biological Psychiatry - Volume 64, Issue 8, 15 October 2008, Pages 708-717