Loss of Glial Cells of the Hippocampus in a Rat Model of Post-traumatic Stress Disorder

Single prolonged stress (SPS) rats is a rodent model of post traumatic stress disorder (PTSD). Abnormal hippocampal morphology and function were found in the PTSD patients. Our previous study has shown that SPS induce loss of hippocampal neurons. But the effects of SPS on glial cells in the hippocampus have not been evaluated. In the present study, wistar male rats were examined at 1, 4, 7, or 14 days after SPS. The morris water maze were performed to examine hippocampal-dependent cognition. The neurometabolite and morphological change in the hippocampal neurons and glial cells were investigated using in vivo proton magnetic resonance spectroscopy and transmission electron microscopy. Immunofluorescence histochemistry and western blotting for Glial fibrillary acidic protein (GFAP) was used to evaluate change of astrocytes. SPS rats showed increased escape latency. The significant reductions in N-acetylaspartate, creatine, and choline-containing compounds in the hippocampus of SPS rats were found. Moreover, abnormal morphological characteristics in glial cells of the SPS group were observed. The number of GFAP-positive cells, intensity of GFAP-ir and GFAP-protein within the hippocampus increased after SPS at 1 day, and then decreased. The findings suggested that SPS induced loss/impairment of glial cell in the hippocampus; also loss of glial cells may due to the astrocytes reduction within the hippocampus of SPS rats.