title: Increased expression of c-fos mRNA and AP-1 transcription factors after cortical impact injury in rats.
abstract: Levels of c-fos mRNA and AP-1 transcription factors co-expression were measured in a controlled lateral cortical impact model of traumatic brain injury (TBI) in rats. Ipsilateral cerebral cortex and bilateral hippocampal c-fos mRNA increases were revealed by in situ hybridization after lateral cortical impact injury. Based on regional in situ hybridization data, we employed semi-quantitative RT-PCR methods to study the temporal profile of changes in the ipsilateral cortex at the site of injury. We found that TBI produces transient increases of c-fos mRNA expression in the ipsilateral cerebral cortex at 5 min postinjury, which peaks at 1 h postinjury and subsides by 1 day postinjury. Gel shift nuclear protein binding assays showed that AP-1 transcription factor binding was robustly increased in injured cerebral cortex at 1 h, 3 h, 5 h and 1 day after injury. These data indicate that TBI can produce significant increases in c-fos expression and subsequent upregulation of the AP-1 transcription factors. Thus, AP-1 transcription factors modulation of downstream gene expression may be an important component of pathophysiological responses to TBI.
authors.affiliation: Department of Neurosurgery, University of Texas Health Sciences Center at Houston 77030.
authors.forename: K
authors.initials: K
authors.lastname: Yang
authors.forename: X S
authors.initials: XS
authors.lastname: Mu
authors.forename: J J
authors.initials: JJ
authors.lastname: Xue
authors.forename: J
authors.initials: J
authors.lastname: Whitson
authors.forename: A
authors.initials: A
authors.lastname: Salminen
authors.forename: C E
authors.initials: CE
authors.lastname: dixon
authors.forename: P K
authors.initials: PK
authors.lastname: Liu
authors.forename: R L
authors.initials: RL
authors.lastname: Hayes
mesh_terms: D000818:Animals; D001483:Base Sequence; D002540:Cerebral Cortex / Q000293:injuries* / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000378:metabolism; D016762:Genes, fos; D006624:Hippocampus / Q000293:injuries / Q000378:metabolism; D008297:Male; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins / Q000096:biosynthesis*; D012333:RNA, Messenger / Q000096:biosynthesis*; D051381:Rats; D017207:Rats, Sprague-Dawley; D018808:Transcription Factor AP-1 / Q000096:biosynthesis*
chemical_list: D004268:DNA-Binding Proteins; D009419:Nerve Tissue Proteins; D012333:RNA, Messenger; D018808:Transcription Factor AP-1