title: Observation of Distressed Conspecific as a Model of Emotional Trauma Generates Silent Synapses in the Prefrontal-Amygdala Pathway and Enhances Fear Learning, but Ketamine Abolishes those Effects.
abstract: Witnessing pain and distress in others can cause psychological trauma and increase odds of developing PTSD in the future, on exposure to another stressful event. However, the underlying synaptic process remains unknown. Here we report that mice exposed to a conspecific receiving electrical footshocks exhibited enhanced passive avoidance (PA) learning when trained 24 h after the exposure. The exposure activated neurons in the dorsomedial prefrontal cortex (dmPFC) and basolateral amygdala (BLA) and altered synaptic transmission from dmPFC to BLA. It increased amplitude, slowed decay of NMDA receptor-mediated currents, and generated silent synapses. Administration of sub-anesthetic ketamine immediately after the exposure prevented the enhancement of PA learning and silent synapse formation. These findings suggest that ketamine can prevent pathophysiological consequences of psychological trauma.
authors: Virginia Tech Carilion Research Institute, Roanoke, VA, USA.
authors: Wataru
authors: W
authors: Ito
authors: Department of Psychology, University of Virginia, Charlottesville, VA, USA.
authors: Alev
authors: A
authors: Erisir
authors: Virginia Tech Carilion Research Institute, Roanoke, VA, USA.|Department of Biomedical Engineering and Mechanics, School of Biomedical Engineering and Sciences, Virginia Tech, Blacksburg, VA, USA.|Department of Psychiatry and Behavioral Medicine, Virginia Tech Carilion School of Medicine, Roanoke, VA, USA.
authors: Alexei
authors: A
authors: Morozov
mesh_terms: D000818:Animals; D001362:Avoidance Learning / Q000187:drug effects / Q000502:physiology*; D066272:Basolateral Nuclear Complex / Q000187:drug effects / Q000503:physiopathology*; D004195:Disease Models, Animal; D004597:Electroshock; D005239:Fear / Q000187:drug effects / Q000502:physiology; D018698:Glutamic Acid / Q000378:metabolism; D007649:Ketamine / Q000494:pharmacology*; D008297:Male; D057507:Mice, 129 Strain; D008810:Mice, Inbred C57BL; D009434:Neural Pathways / Q000187:drug effects / Q000503:physiopathology; D017397:Prefrontal Cortex / Q000187:drug effects / Q000503:physiopathology*; D011619:Psychotropic Drugs / Q000494:pharmacology*; D018091:Receptors, AMPA / Q000378:metabolism; D016194:Receptors, N-Methyl-D-Aspartate / Q000378:metabolism; D013315:Stress, Psychological / Q000188:drug therapy / Q000503:physiopathology*; D013569:Synapses / Q000187:drug effects / Q000502:physiology; D009435:Synaptic Transmission / Q000187:drug effects / Q000502:physiology; D046509:Tissue Culture Techniques; D014796:Visual Perception
chemical_list: D011619:Psychotropic Drugs; D018091:Receptors, AMPA; D016194:Receptors, N-Methyl-D-Aspartate; D018698:Glutamic Acid; D007649:Ketamine