title: Postsynaptic density protein (PSD)-95 expression is markedly decreased in the hippocampal CA1 region after experimental ischemia-reperfusion injury.
abstract: Synaptic plasticity is important for functional recovery after cerebral ischemic injury. In the present study, we investigated chronological change in the immunoreactivity of PSD-95, a kind of postsynaptic density protein, in the hippocampus proper (CA1-3 regions) after 5 min of transient cerebral ischemia in gerbils. PSD-95 immunoreactivity was observed in MAP-2-immunoreactive dendrites in the CA1-3 regions of the sham group. The PSD-95 immunoreactivity was shown as beaded structure in the MAP-2-immunoreactive dendrites. However, PSD-95 immunoreactivity began to be dramatically decreased in MAP-2-immunoreactive dendrites in the CA1 region, not CA2-3 region, at early time after ischemia-reperfusion. At 5 days after ischemia-reperfusion, MAP-2 immunoreactivity almost disappeared in the ischemic CA1 region, and PSD-95 immunoreactivity was much lower than that in the sham group. In brief, PSD-95 immunoreactivity in the CA1 dendrites was markedly decreased at early time after ischemia-reperfusion. We suggest that decreased PSD-95 immunoreactivity in the ischemic CA1 region may lead to a deficit of postsynaptic plasticity in the brain.
authors.affiliation: Department of Neurobiology, School of Medicine, Kangwon National University, Chuncheon 200-701, South Korea.
authors.forename: Bing Chun
authors.initials: BC
authors.lastname: Yan
authors.forename: Joon Ha
authors.initials: JH
authors.lastname: Park
authors.forename: Ji Hyeon
authors.initials: JH
authors.lastname: Ahn
authors.forename: Jae-Chul
authors.initials: JC
authors.lastname: Lee
authors.forename: Moo-Ho
authors.initials: MH
authors.lastname: Won
authors.forename: Il-Jun
authors.initials: IJ
authors.lastname: Kang
mesh_terms: D000818:Animals; D015153:Blotting, Western; D056547:CA1 Region, Hippocampal / Q000378:metabolism* / Q000473:pathology; D005452:Fluoresceins; D019084:Fluorescent Antibody Technique, Indirect; D005456:Fluorescent Dyes; D005849:Gerbillinae; D007150:Immunohistochemistry; D002546:Ischemic Attack, Transient / Q000378:metabolism / Q000473:pathology; D008297:Male; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism; D009419:Nerve Tissue Proteins / Q000096:biosynthesis* / Q000235:genetics; D009474:Neurons / Q000473:pathology; D015427:Reperfusion Injury / Q000378:metabolism* / Q000473:pathology
chemical_list: D005452:Fluoresceins; D005456:Fluorescent Dyes; D009419:Nerve Tissue Proteins; C435731:fluoro jade; C033652:postsynaptic density proteins; D019950:Mitogen-Activated Protein Kinase 1