Early disturbance of a mitochondrial DNA expression in gerbil hippocampus after transient forebrain ischemia.
The level of mRNA for cytochrome c oxidase subunit I (COX-I), which is encoded by mitochondrial DNA (mtDNA), progressively decreased in the hippocampal CA1 neurons of gerbils from 1-3 h of the reperfusion after 3.5 min of transient forebrain ischemia, and completely disappeared at 7 days. The activity of cytochrome c oxidase (COX) protein also showed the early decrease in the CA1 cells, and was followed by the reduction of the level of COX-I DNA after 2 days. However, the activity of succinic dehydrogenase (SDH), a mitochondrial enzyme that is encoded by nuclear DNA, maintained normal activity until 1 day in the CA1 cells, and significantly decreased at 7 days. These results suggest that the early onset and the progressive disturbance of a mitochondrial DNA expression found selectively in the CA1 neurons could cause progressive failure of energy production of the cells that eventually results in the neuronal cell death.
Abe
K
K
Department of Neurology, Tohoku University School of Medicine, Sendai, Japan.
Kawagoe
J
J
Kogure
K
K
D000818:Animals; D015152:Blotting, Northern; D015139:Blotting, Southern; D002540:Cerebral Cortex / Q000378:metabolism; D004272:DNA, Mitochondrial / Q000096:biosynthesis*; D003576:Electron Transport Complex IV / Q000096:biosynthesis; D005849:Gerbillinae; D006624:Hippocampus / Q000378:metabolism*; D017403:In Situ Hybridization; D002546:Ischemic Attack, Transient / Q000378:metabolism*; D008297:Male; D012333:RNA, Messenger / Q000096:biosynthesis; D013385:Succinate Dehydrogenase / Q000378:metabolism
D004272:DNA, Mitochondrial; D012333:RNA, Messenger; D013385:Succinate Dehydrogenase; D003576:Electron Transport Complex IV