Neurochemical Research

, Volume 39, Issue 4, pp 741–747 | Cite as

The Unfolded Protein Response is Triggered in Rat Neurons of the Dorsal Raphe Nucleus After Single-Prolonged Stress

  • Juhua Xie
  • Fang Han
  • Yuxiu Shi
Original Paper


The dorsal raphe nucleus (DRN) has been suggested playing an important role in the pathophysiology of post-traumatic stress disorder (PTSD), however the underlying cellular mechanisms are not fully understood. The endoplasmic reticulum (ER) is a critical organelle for synthesis of membrane and secretory proteins, and perturbations in ER lead to the unfolded protein response (UPR). In the present experiment, we hypothesized UPR may be associated with the PTSD, and there is an induction of UPR in the DRN neurons of the PTSD-like rats. We first observed the morphological changes of ER in the DRN neurons of the rats exposed to single-prolonged stress (SPS), a model of PTSD, and then we also detected the expression of ER chaperones glucose regulated protein 78 (GRP78) and glucose regulated protein (GRP94) which are two key sensors and mediators of the UPR and are considered an ER stress-specific inducible proteins using methods of western blot and immunohistochemical analysis. Our results demonstrated there were abnormal expansion of ER and up-regulation expression of GRP78 and GRP94 after SPS, which indicated that the UPR was triggered in the DRN neurons of the PTSD-like rats. These results are consistent with our speculation that UPR may be associated with the PTSD, and suggest us the UPR may be a new critical cellular mechanisms of PTSD.


Single-prolonged stress Post-traumatic stress disorder Glucose regulated protein 78 Glucose regulated protein 94 Dorsal raphe nucleus 



The authors are grateful to all of the staff members of the China Medical University Experiment Center for their technical support. In addition, this research was supported by a grant from the National Natural Science Foundation of China (No. 81171282 and No. 31200772) and China National Doctoral Fund (No. 20132104110021).

Conflict of interest

The authors indicate no potential conflicts of interest.


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Copyright information

© Springer Science+Business Media New York 2014

Authors and Affiliations

  1. 1.Laboratory of Post-Traumatic Stress Disorder, Department of Histology and Embryology, Institute of Pathology and Pathophysiology, Basic Medical Sciences CollegeChina Medical UniversityShenyangPeople’s Republic of China

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