Traumatic Stress Produces Distinct Activations of GABAergic and Glutamatergic Neurons in Amygdala

Abstract

Posttraumatic stress disorder (PTSD) is an anxiety disorder characterized by intrusive recollections of a severe traumatic event and hyperarousal following exposure to the event. Human and animal studies have shown that the change of amygdala activity after traumatic stress may contribute to occurrences of some symptoms or behaviors of the patients or animals with PTSD. However, it is still unknown how the neuronal activation of different sub-regions in amygdala changes during the development of PTSD. In the present study, we used single prolonged stress (SPS) procedure to obtain the animal model of PTSD, and found that 1 day after SPS, there were normal anxiety behavior and extinction of fear memory in rats which were accompanied by a reduced proportion of activated glutamatergic neurons and increased proportion of activated GABAergic neurons in basolateral amygdala (BLA). About 10 days after SPS, we observed enhanced anxiety and impaired extinction of fear memory with increased activated both glutamatergic and GABAergic neurons in BLA and increased activated GABAergic neurons in central amygdala (CeA). These results indicate that during early and late phase after traumatic stress, distinct patterns of activation of glutamatergic neurons and GABAergic neurons are displayed in amygdala, which may be implicated in the development of PTSD.

Traumatic Stress Produces Delayed Alterations of Synaptic Plasticity in Basolateral Amygdala

“…But the biological basis underlying PTSD was unclear. Single prolonged stress (SPS) model, an appropriate PTSD model of animal, has been established to explore the neurobiological mechanisms of PTSD considering the limitations of human studies (Souza et al, 2017; Fang et al, 2018). Rats exhibited abnormal behavior as well as hypothalamic-pituitary-adrenal (HPA)-axis dysfunction following SPS (Ding et al, 2010), which is a putative neuroendocrinological hallmark of PTSD (Mellman et al, 2009; Hughes and Shin, 2011; Pratchett et al, 2011; Bailey et al, 2013).…”

Study on the mechanism of TMRK electroacupuncture in repairing synaptic plasticity in amygdala and hippocampus to relieve fear memory in PTSD rats

“…In the current experimental protocol, each rat was first restrained via placement inside a plastic tube for 2 hours, immediately following restraint, each rat underwent a 20-min forced swim, after the forced swim and placement in a cage for 15 minutes, each rat was anesthetized with ether in a cylinder until losing consciousness. The SPS procedure was based on previous studies [6]. After modeling, the rat was returned to its cage, and was conventionally housed/fed until later experiments were conducted.…”

“…Some drugs, for example, selective serotonin reuptake inhibitors, have been used for the first-line treatments for PTSD [4, 5]. Nevertheless, there is still a subgroup of PTSD patients who have some persistent symptoms or maintain conditioned fear responses to threatens,and finally the disease becomes chronic [6].…”

Post-retrieval Extinction Prevents Reconsolidation of Methamphetamine Memory Traces and Subsequent Reinstatement of Methamphetamine Seeking

“…Immunofluorescence assays were performed to examine Fos expressions in brain slices based on our previous studies (Xue et al, 2017; Fang et al, 2018). Rats were anesthetized with 10% chloral hydrate and perfused transcardially with 0.01 M phosphate buffered saline (PBS) followed by 4% paraformaldehyde (PFA).…”

“…Images were acquired by a fluorescence microscope (VS120, Olympus) with a 20× objective lens. The number of Fos-, NeuN-, and double-labeled cells was quantified in a blind fashion according to our previous studies (Xue et al, 2017; Fang et al, 2018). In brief, we selected at least three slices for each brain region of each rat and averaged the proportions of neurons expressing Fos on either side of the specific brain region to be the percentage of neuronal activation for each rat and measured the number of Fos-, NeuN-, and double-labeled cells using Image-Pro Plus software.…”