title: Stress protein inductions after brain ischemia.
abstract: 1. Hippocampal CA1 neurons are the most vulnerable to transient cerebral ischemia. However, the mechanism has not been fully understood. 2. The mRNAs for 72-kd (HSP72) and 73-kd (HSC73) heat shock proteins (HSPs), which are located mainly in the cytoplasm, were greatly induced together in CA1 cells, with a peak at 1-2 days in gerbils. However, immunoreactive HSP72 protein was only minimally expressed in CA1 neurons. 3. The mRNA for mitochondrial HSP60 began to increase at 3 hr in CA1 cells and was sustained until 1 day. 4. The level of mRNA for cytochrome c oxidase subunit I (COX-I) progressively decreased in CA1 neurons after a transient ischemia and completely disappeared at 7 days. The activity of cytochrome c oxidase (COX) protein also showed an early decrease in CA1 cells and was followed by a reduction in the level of COX-I DNA after 2 days. 5. These results suggest that HSP gene inductions were inhibited at the translational level but that mitochondrial DNA expression was disturbed at the transcriptional level. A disturbance of mitochondrial DNA expression could cause progressive failure of energy production of CA1 cells that eventually results in neuronal cell death.
authors.affiliation: Department of Neurology, Tohoku University School of Medicine, Sendai, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Abe
authors.forename: J
authors.initials: J
authors.lastname: Kawagoe
authors.forename: M
authors.initials: M
authors.lastname: Aoki
authors.forename: K
authors.initials: K
authors.lastname: Kogure
authors.forename: Y
authors.initials: Y
authors.lastname: Itoyama
mesh_terms: D000818:Animals; D001921:Brain / Q000378:metabolism*; D018834:Chaperonin 60 / Q000235:genetics; D003576:Electron Transport Complex IV / Q000235:genetics; D005786:Gene Expression Regulation; D005849:Gerbillinae; D050883:HSC70 Heat-Shock Proteins; D018840:HSP70 Heat-Shock Proteins; D050884:HSP72 Heat-Shock Proteins; D006360:Heat-Shock Proteins / Q000096:biosynthesis / Q000235:genetics*; D006624:Hippocampus / Q000378:metabolism; D002546:Ischemic Attack, Transient / Q000235:genetics / Q000378:metabolism*; D008297:Male; D008928:Mitochondria / Q000378:metabolism; D014158:Transcription, Genetic
chemical_list: D018834:Chaperonin 60; D050883:HSC70 Heat-Shock Proteins; D018840:HSP70 Heat-Shock Proteins; D050884:HSP72 Heat-Shock Proteins; D006360:Heat-Shock Proteins; D003576:Electron Transport Complex IV