title: Brief fear preexposure facilitates subsequent fear conditioning.
abstract: Post-traumatic stress disorder (PTSD) is an anxiety disorder that occurs following an unexpected exposure to a severe psychological event. A history of a brief trauma is reported to affect a risk for future PTSD development; however, little is known about the mechanisms by which a previous trauma exposure drives the sensitivity to a late-coming trauma. Using a mouse PTSD model, we found that a prior foot shock enhances contextual fear conditioning. This shock-induced facilitation of fear conditioning (i.e., priming effect) persisted for 7 days and was prevented by MK801, an N-methyl-D-aspartate receptor antagonist. Other types of trauma, such as forced swimming or tail pinch, did not induce a priming effect on fear conditioning. Thus, a trauma is unlikely generalized to modify the sensitivity to other traumatic experiences. The behavioral procedure employed in this study may be a useful tool to elucidate the etiology of PTSD.
authors: Graduate School of Pharmaceutical Sciences, University of Tokyo, Tokyo 113-0033, Japan.
authors: Satoshi
authors: S
authors: Iwasaki
authors: Graduate School of Pharmaceutical Sciences, University of Tokyo, Tokyo 113-0033, Japan.
authors: Tetsuya
authors: T
authors: Sakaguchi
authors: Graduate School of Pharmaceutical Sciences, University of Tokyo, Tokyo 113-0033, Japan; Center for Information and Neural Networks, Suita City, Osaka 565-0835, Japan. Electronic address: ikegaya@mol.f.u-tokyo.ac.jp.
authors: Yuji
authors: Y
authors: Ikegaya
mesh_terms: D000818:Animals; D001007:Anxiety / Q000523:psychology; D003214:Conditioning, Classical / Q000187:drug effects / Q000502:physiology; D016291:Dizocilpine Maleate / Q000494:pharmacology; D004597:Electroshock; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology; D005239:Fear / Q000502:physiology / Q000523:psychology*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D010146:Pain / Q000523:psychology; D013313:Stress Disorders, Post-Traumatic / Q000503:physiopathology / Q000523:psychology*; D013315:Stress, Psychological / Q000503:physiopathology / Q000523:psychology
chemical_list: D018691:Excitatory Amino Acid Antagonists; D016291:Dizocilpine Maleate
keywords: Fear conditioning; Mouse; N-methyl-d-aspartate receptor; Post traumatic stress disorder; Trauma