title: Excitatory amino acid receptor subtype binding following traumatic brain injury.
abstract: Sprague-Dawley rats were subjected to a moderate level (2.2 atm) of traumatic brain injury (TBI) using fluid percussion. Injured animals were allowed post-trauma survival periods of 5 min, 3 and 24 h. Regional glutamate receptor subtype binding was assessed with quantitative autoradiography in each group for N-methyl-D-aspartate (NMDA), quisqualate and kainate receptor subpopulations at approximately the -3.8 bregma level and compared to a sham control group. [3H]glutamate binding to the NMDA receptor was significantly (P less than 0.05) decreased at 3 h post-TBI in the hippocampal CA1 stratum radiatum, the molecular layers of the dentate gyri and the outer (layers 1-3) and inner (layers 5 and 6) overlying neocortex. NMDA receptor binding was significantly reduced in layers 5 and 6 of the neocortex at all post-trauma survival times but no further differences were seen in the hippocampi. No significant changes were observed with [3H]AMPA binding to quisqualate receptors and [3H]KA binding was significantly reduced only in layers 5 and 6 of the neocortex at 24 h after TBI. These data further confirm the pathological involvement of the NMDA receptor complex in brain regions selectively vulnerable to moderate levels of TBI in this model.
authors.affiliation: Neuroscience Laboratory, Veterans Administration Medical Center, Washington, DC 20422.
authors.forename: L P
authors.initials: LP
authors.lastname: Miller
authors.forename: B G
authors.initials: BG
authors.lastname: Lyeth
authors.forename: L W
authors.initials: LW
authors.lastname: Jenkins
authors.forename: L
authors.initials: L
authors.lastname: Oleniak
authors.forename: D
authors.initials: D
authors.lastname: Panchision
authors.forename: R J
authors.initials: RJ
authors.lastname: Hamm
authors.forename: L L
authors.initials: LL
authors.lastname: Phillips
authors.forename: C E
authors.initials: CE
authors.lastname: Dixon
authors.forename: G L
authors.initials: GL
authors.lastname: Clifton
authors.forename: R L
authors.initials: RL
authors.lastname: Hayes
mesh_terms: D000818:Animals; D001930:Brain Injuries / Q000378:metabolism*; D007608:Kainic Acid; D010069:Oxadiazoles; D051381:Rats; D011919:Rats, Inbred Strains; D018091:Receptors, AMPA; D018092:Kainic Acid Receptors; D016194:Receptors, N-Methyl-D-Aspartate / Q000378:metabolism*; D017981:Receptors, Neurotransmitter / Q000378:metabolism*
chemical_list: D007608:Kainic Acid; D010069:Oxadiazoles; D018091:Receptors, AMPA; D018092:Kainic Acid Receptors; D016194:Receptors, N-Methyl-D-Aspartate; D017981:Receptors, Neurotransmitter