Post-ischemic transcriptional and translational responses of EC-SOD in mouse brain and serum.
Extracellular superoxide dismutase (EC-SOD) is neuroprotective, but its role in cerebral ischemia remains to be determined. We herein describe the topographical localization and quantitative changes in EC-SOD and its mRNA expression following cerebral ischemia in mice. Mice were subjected to transient forebrain ischemia and varied intervals of reperfusion. The measurements of EC-SOD using ELISA showed increased brain EC-SOD after 24 h of reperfusion and an increase in EC-SOD brain/serum ratio after 3 h. The immunohistochemical examination in normal mice showed strong EC-SOD immunoreactivity in the choroid plexus, pia mater, and ventral tuberal area of the hypothalamus. EC-SOD immunoreactivity in cortical and striatal capillary wall was conspicuous after 3 h. EC-SOD immunoreactivity was also noted in cortical neurons after 24 h. Northern blot analysis showed an increased EC-SOD mRNA expression in the brain after 24 h. An in situ hybridization study in normal mice demonstrated the mRNA expression of EC-SOD in choroid plexus and neurons through the brain especially in the cortex or ventral tuberal area of the hypothalamus, but demonstrated no mRNA expression of EC-SOD in the capillary wall. These findings suggest that EC-SOD accumulates on endothelial cells in response to this injury by an unknown mechanism, while cortical neurons produce EC-SOD themselves after cerebral ischemia with reperfusion.
Fukui
Shinji
S
Department of Neurosurgery, National Defense Medical College, Tokorozawa, Japan. grd1309@gr.ndmc.ac.jp
Ookawara
Tomomi
T
Nawashiro
Hiroshi
H
Suzuki
Keiichiro
K
Shima
Katsuji
K
D000818:Animals; D001921:Brain / Q000201:enzymology / Q000473:pathology; D002545:Brain Ischemia / Q000201:enzymology* / Q000235:genetics*; D004797:Enzyme-Linked Immunosorbent Assay; D005110:Extracellular Space / Q000201:enzymology; D015971:Gene Expression Regulation, Enzymologic; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D014176:Protein Biosynthesis; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D013482:Superoxide Dismutase / Q000097:blood* / Q000235:genetics / Q000378:metabolism*; D014158:Transcription, Genetic
D012333:RNA, Messenger; D013482:Superoxide Dismutase