title: Single prolonged stress decreases glutamate, glutamine, and creatine concentrations in the rat medial prefrontal cortex.
abstract: Application of single prolonged stress (SPS) in rats induces changes in neuroendocrine function and arousal that are characteristic of post traumatic stress disorder (PTSD). PTSD, in humans, is associated with decreased neural activity in the prefrontal cortex, increased neural activity in the amygdala complex, and reduced neuronal integrity in the hippocampus. However, the extent to which SPS models these aspects of PTSD has not been established. In order to address this, we used high-resolution magic angle spinning proton magnetic resonance spectroscopy (HR-MAS (1)H MRS) ex vivo to assay levels of neurochemicals critical for energy metabolism (creatine and lactate), excitatory (glutamate and glutamine) and inhibitory (gamma amino butyric acid (GABA)) neurotransmission, and neuronal integrity (N-acetylaspartate (NAA)) in the medial prefrontal cortex (mPFC), amygdala complex, and hippocampus of SPS and control rats. Glutamate, glutamine, and creatine levels were decreased in the mPFC of SPS rats when compared to controls, which suggests decreased excitatory tone in this region. SPS did not alter the neurochemical profiles of either the hippocampus or amygdala. These data suggest that SPS selectively attenuates excitatory tone, without a disruption of neuronal integrity, in the mPFC.
authors.affiliation: Department of Psychiatry, University of Michigan, Ann Arbor, MI, United States. dayank@med.umich.edu
authors.forename: Dayan
authors.initials: D
authors.lastname: Knox
authors.forename: Shane A
authors.initials: SA
authors.lastname: Perrine
authors.forename: Sophie A
authors.initials: SA
authors.lastname: George
authors.forename: Matthew P
authors.initials: MP
authors.lastname: Galloway
authors.forename: Israel
authors.initials: I
authors.lastname: Liberzon
mesh_terms: D000679:Amygdala / Q000378:metabolism; D000818:Animals; D001224:Aspartic Acid / Q000031:analogs & derivatives / Q000378:metabolism; D003401:Creatine / Q000378:metabolism*; D004734:Energy Metabolism; D018698:Glutamic Acid / Q000378:metabolism*; D005973:Glutamine / Q000378:metabolism*; D006624:Hippocampus / Q000378:metabolism; D019344:Lactic Acid / Q000378:metabolism; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D017397:Prefrontal Cortex / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013313:Stress Disorders, Post-Traumatic / Q000378:metabolism; D013315:Stress, Psychological / Q000378:metabolism; D009435:Synaptic Transmission; D005680:gamma-Aminobutyric Acid / Q000378:metabolism
chemical_list: D005973:Glutamine; D001224:Aspartic Acid; D019344:Lactic Acid; D018698:Glutamic Acid; D005680:gamma-Aminobutyric Acid; C000179:N-acetylaspartate; D003401:Creatine