PET Mapping of Neurofunctional Changes in a Post-traumatic Stress Disorder Model

Abstract

Post-traumatic stress disorder (PTSD) is an anxiety disorder that occurs following exposure to a traumatic event. This study aims to investigate the neurobiological changes of PTSD by positron emission tomography (PET) in a rat model. Methods: Serial ¹⁸F-FDG small animal PET imaging studies were performed after the control (tone presentation), fear conditioning and extinction retrieval phases. Neuroactivity marker c-Fos protein was used for immunostaining. Results: Increased glucose metabolism was observed in the bilateral amygdale after fear conditioning (P < 0.001), and in the right posterior insular cortex after extinction retrieval (P < 0.001) compared with the control phase. Increased c-Fos expression was found in the posterior insular cortex after extinction retrieval compared with the control phase (P < 0.01). Conclusion: Our results demonstrated neurofunctional changes associated with PTSD. The amygdala plays a key role in fear memory formation, and insular cortex is related to the retrieval of extinction memory.