Original article| Volume 60, ISSUE 7, P767-776, October 01, 2006

Anisomycin, a Protein Synthesis Inhibitor, Disrupts Traumatic Memory Consolidation and Attenuates Posttraumatic Stress Response in Rats

  • Hagit Cohen
    Address reprint requests to Hagit Cohen, Ph.D., Anxiety and Stress Research Unit, Ministry of Health Mental Health Center, Faculty of Health Sciences, Ben-Gurion University of the Negev, P.O. Box 4600, Beer-Sheva 84170 Israel
    Ministry of Health Mental Health Center, Anxiety and Stress Research Unit, Faculty of Health Sciences, Ben Gurion University of the Negev, Beer Sheva
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  • Zeev Kaplan
    Ministry of Health Mental Health Center, Anxiety and Stress Research Unit, Faculty of Health Sciences, Ben Gurion University of the Negev, Beer Sheva
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  • Michael A. Matar
    Ministry of Health Mental Health Center, Anxiety and Stress Research Unit, Faculty of Health Sciences, Ben Gurion University of the Negev, Beer Sheva
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  • Uri Loewenthal
    Ministry of Health Mental Health Center, Anxiety and Stress Research Unit, Faculty of Health Sciences, Ben Gurion University of the Negev, Beer Sheva
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  • Nitsan Kozlovsky
    Ministry of Health Mental Health Center, Anxiety and Stress Research Unit, Faculty of Health Sciences, Ben Gurion University of the Negev, Beer Sheva
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  • Joseph Zohar
    Division of Psychiatry, State of Israel Ministry of Health, Chaim Sheba Medical Center, Ramat Gan

    Sackler Medical School, Tel Aviv University, Tel Aviv, Israel.
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      Paradoxical changes in memory represent a troublesome characteristic of posttraumatic stress disorder (PTSD). Exceptionally vivid intrusive memories of some aspects of the trauma are mingled with patchy amnesia regarding other important aspects. Molecular studies of the memory process suggest that the conversion from labile short-term memory into long-term fixed traces involves protein synthesis. This study assessed the effects of administration of anisomycin, a protein synthesis inhibitor, after initial exposure, after exposure to a cue associated with triggering experience, and after reexposure to the triggering trauma in an animal model of PTSD.


      Magnitude of changes in prevalence of anxiety-like behaviors on the elevated plus-maze and nonhabituated exaggerated startle reaction were compared in rats that were exposed to predator stress, with and without microinjection of anisomycin.


      Microinjection of anisomycin before and after stress exposure reduced anxiety-like and avoidant behavior, reduced the mean startle amplitude, and reversed the stress-induced habituation deficit 7 days later. The persistent anxiety-like behaviors that were seen after stress exposure do not appear to be sensitive to anisomycin after reexposure to a cue associated with the event or after reexposure to the index experience.


      Disruption of the process of traumatic memory consolidation may be useful for mitigating PTSD symptoms.

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