Posttraumatic stress disorder (PTSD) is a prevalent psychiatric disorder. Several studies have attempted to characterize molecular alterations associated with PTSD, but most findings were limited to the investigation of specific cellular markers in the periphery or defined brain regions. In the current study, we aimed to unravel affected molecular pathways/mechanisms in the fear circuitry associated with PTSD. We interrogated a foot shock induced-PTSD mouse model by integrating proteomics and metabolomics profiling data. Alterations at the proteome level were analyzed using in vivo 15N metabolic labeling combined with mass spectrometry in prelimbic cortex (PrL), anterior cingulate cortex (ACC), basolateral amygdala (BLA), central nucleus of amygdala (CeA) and CA1 of hippocampus between shocked and non-shocked (control) mice, with and without fluoxetine treatment.